Borderline personality disorder - A compassionate guide to what BPD is, how it develops, and how treatment can help

Borderline personality disorder, often shortened to BPD and otherwise known as emotionally unstable personality disorder (EUPD), is one of the most misunderstood diagnoses in mental health. It is also one of the most stigmatised in my opinion.

Even the label is contentious as whilst for some people it can be a way to understand themselves and to seek treatment, historically the condition was considered ‘untreatable’ and people with the diagnosis were literally ‘written off’ by services.  Now for many people, even hearing the label can bring up shame, fear, or dread.

Research continues to show that stigma around BPD is widespread and can affect the quality-of-care people receive.  It is a harsh reality that many clinicians either choose not to or are ill-equipped to work with people with BPD which leaves both clinicians and people with BPD with a sense of failure or doom, not of their own making.

I want to write about BPD in a different way. I want to write about it in a way that is compassionate, clear, and rooted in real clinical understanding and my experience of working with people with BPD.

That means being honest about how painful and disruptive it can be, both for the person with BPD and those around them, because it can involve extreme behaviours such as self-harm, suicidality, and big emotional outbursts.

It also means being very clear that this is not about blame. People do not develop these patterns because they are bad, weak, or intentionally harmful. These patterns usually make much more sense when we understand emotional sensitivity, attachment, trauma, invalidation, coping, and a nervous system trying desperately to do what it thinks it must, to survive and stay connected.

In my own work within the NHS, I chose to specialise in working with people with BPD on the emotion regulation pathway.  I found the work rewarding and meaningful and those diagnosed with the condition, empathic, intelligent, funny and engaging, but also often overwhelmed and let down.

Amongst my qualifications, I have a post graduate diploma in dialectical behaviour therapy (DBT), which is the evidence-based treatment for BPD, and that has shaped the way I think about intense emotions, self-harm, impulsive coping, relationship instability, and the very real possibility of change. The DBT-informed lens helped me to not ask “what is wrong with this person?” but “what happened to them, what is happening now, what function does their behaviour serve, and what skills and support are needed now?”

What’s in a name?

Some people dislike the word borderline because it feels outdated or unclear. I mean borderline what? 

The word “borderline” is an old psychiatric term, and it is not a very helpful one. Historically, it came from the idea that some people seemed to sit on the “borderline” between neurosis and psychosis. In older psychiatric language, neurosis referred to distress such as anxiety, depression, or emotional conflict where the person remained broadly in touch with reality. Psychosis referred to experiences such as delusions, hallucinations, or a more significant loss of contact with reality.

People who were later described as having borderline personality disorder did not fit neatly into either category. They could appear highly emotionally distressed, relationally insecure, impulsive, or self-destructive, but they might also have brief periods of paranoia, dissociation, or feeling unreal, especially under extreme stress. So the term “borderline” was used to describe this supposed in-between state.

This is one reason some people prefer the term Emotionally Unstable Personality Disorder, used in ICD systems, although that label also has problems. Others argue for more trauma-informed or formulation-based language, because “borderline” tells us very little about what the person has lived through or what support they actually need. 

Others, me included, struggle with the phrase ‘personality disorder’ because it can sound as though the whole person, their personality, their character, is disordered, rather than recognising a pattern of difficulties, that developed over time by events beyond their control.

This matters, because people with BPD can be described in dismissive or blaming ways. Words such as “attention seeking”, “manipulative”, “dramatic”, or “difficult” still appear far too often in everyday conversation and, sadly in my experience, far too often in services too.

What do I think?  Well there is a lot to be argued about any mental health label and that will be for another blog.  For some it helps to put a name to their experience and to access services.  Other people feel labels restrict and negatively define us and are nothing more than social constructs.

Personally, I believe that with any struggle physical or mental it can help to understand the underlying symptomology and causation.  For example, if I had arthritis, knowing this would help myself and others to know I might be in pain, and why, and to get the correct treatment.  Labels can do that, but they need to be carefully considered. 

Ultimately BPD is an issue surrounding past events and very often attachments, not personality, so let’s push towards something that understands more about what this really is, such as attachment response.

So what is borderline personality disorder?

Borderline personality disorder refers to a pattern of significant difficulties involving emotions, relationships, self-image, and behavioural control. In diagnostic terms, it is defined as a pervasive pattern of instability in interpersonal relationships, self-image, mood and emotion, with marked impulsivity.  These patterns should have begun by early adulthood and be present across contexts of the person’s life.

Diagnosis is based on meeting at least five out of nine criteria, which is one reason two people with the same diagnosis may look quite different in real life dependent on which five they meet.

That is worth pausing on. BPD is not one single presentation. One person may appear outwardly reactive, impulsive, and chaotic in relationships. Another may seem quiet, high functioning, and held together on the outside, but experience intense shame, emptiness, and self-destructive urges in private. Another may cope well professionally while repeatedly unravelling in close relationships. The diagnosis captures a cluster of patterns, but it does not tell the full human story.

This is why a good assessment should never stop at ticking boxes. Current clinical guidance recommends a full assessment that considers symptoms, relationships, risk, trauma history, co-occurring conditions, strengths, functioning, past treatment, and the person’s own goals.

Sadly, I have seen many people mislabelled, often by clinicians neither qualified or trained to understand either the label or the damage that mislabelling can do. Diagnosis should really only be made by a psychiatrist or a clinical psychologist.

The core features of BPD

Although each person’s experience is different, there are several themes that commonly run through BPD.

One of the central features is emotional dysregulation. Feelings can rise quickly even to seemingly small events, become overwhelming, and take a long time to settle (even days and weeks). What other people may see as a small trigger can feel internally like a major emotional emergency. A text left unanswered, a perceived criticism, a shift in tone, or a sense of distance in a relationship can trigger panic, shame, rage, or despair.

Another key feature is the fear of abandonment, whether real or perceived. This can show up as panic when somebody pulls away, desperate attempts to stop someone leaving, intense protest behaviour, or pushing someone away first to avoid being the one abandoned.

Relationships often feel intense and unstable. A person may feel deeply attached very quickly, idealise someone, then swing into anger, hurt, or distrust when they feel let down. These patterns are often described clinically as instability in relationships, but underneath them is usually a high degree of attachment sensitivity and difficulty holding onto a steady sense of another person when emotions run high.

Sense of self can also be fragile or unstable. Some people describe not knowing who they are, what they believe, or how they want to live and often take on elements and ideas from people around them. Others describe chronic emptiness, loneliness, or a persistent sense that something is missing inside that often only another person can fill.

Impulsivity is another common feature. This might involve spending, substance use, binge eating, risky sex, dangerous driving, self-harm, or sudden drastic decisions. Under high stress, some people also experience dissociation or transient paranoid thinking.

The diagnostic criteria in plain English

The formal diagnostic criteria are useful, but they can sound abstract. So let’s put them into more human language.

1.    A person may make frantic efforts to avoid real or imagined abandonment. In practice, this may look like feeling unable to tolerate distance, becoming panicked when someone seems unavailable, or going to great lengths to stop a perceived rejection.

2.    There may be a pattern of unstable and intense relationships, often swinging between idealisation and devaluation. In ordinary life, this can mean feeling somebody is wonderful, safe, or perfect one day, then feeling devastated, furious, or convinced they do not care after a rupture or disappointment.

3.    There may be identity disturbance, meaning a markedly unstable sense of self. This can involve confusion about values, goals, sexuality, career direction, or self-worth, or feeling like a different person depending on who one is with.

4.    There may be impulsivity in areas that are potentially self-damaging, such as sex, spending, substances, binge eating, or reckless behaviour.

5.    There may be recurrent suicidal behaviour, self-harm, threats, or gestures, especially during times of intense distress or perceived abandonment.

6.    Affective instability is another criterion. This means rapid shifts in mood and emotional reactivity rather than simple “moodiness”. The feelings are usually powerful and tied to triggers, especially interpersonal ones.

7.    Many people also report chronic feelings of emptiness, which can feel like numbness, hollowness, disconnection, or painful inner absence.

8.    There can be intense anger or difficulty controlling anger. Sometimes this comes outward as arguments, shouting, or rage. Sometimes it is turned inward and becomes self-hatred or brutal self-criticism.

9.    Finally, there may be transient stress-related paranoid thinking or dissociation. In moments of high distress, the person may feel unreal, detached, suspicious, foggy, or disconnected from their body or surroundings.

Because diagnosis requires five out of nine criteria, there is a lot of variation in how BPD presents. That is why diagnosis should always be paired with formulation. The label is not enough on its own and only psychologists or psychiatrists should really be making this judgement call.

Thinking in domains can be more helpful than thinking in labels

Although diagnostic criteria are important, I often find it more helpful clinically to think in domains. In other words, what broad areas are causing this person the most pain and difficulty?

1.    The first domain is emotion regulation. This is often the core pathway. The person may feel emotions quickly, intensely, and for longer than other people expect. They may struggle to identify what they are feeling until the emotion is already overwhelming. They may need support to notice body signals, slow down, and find safer ways of responding.

2.    The second domain is relationships and attachment. Many people with BPD are highly sensitive to signs of withdrawal, criticism, distance, or inconsistency. Relationships can become the place where emotional pain is most activated and where old fears of rejection or abandonment are repeatedly triggered.

3.    The third domain is identity and self-experience. A person may seem successful, capable, or articulate on the outside, while internally feeling empty, broken, unreal, or uncertain who they are. ICD-11 descriptions of the borderline pattern continue to emphasise instability in relationships, self-image, and emotions, along with fears of abandonment and self-harming impulsivity.

4.    The fourth domain is behavioural regulation. This includes self-harm, suicidal crises, impulsive coping, substance use, disordered eating patterns, or other urgent attempts to escape or manage overwhelming states.

5.    The fifth domain is cognition under stress. When emotions are high, thinking can become black and white, suspicious, dissociated, or rigid. The person may “know” one thing when calm and believe something very different when distressed.

Thinking in domains helps shift the conversation from judgment to understanding. Instead of asking “what label fits?” we start asking “where is this person hurting, what keeps the cycle going, and what will genuinely help?”

Transactional causation and the biosocial model

I believe that the transactional biosocial model is one of the most helpful ways to understand how BPD develops because no-one is born with BPD, and in fact a diagnosis really shouldn’t be given to anyone under 18 years of age, although I often find it is.  Again, I go back to my experience that so many diagnoses are made by people that are not qualified or trained to do so.

The biosocial model, which strongly informs DBT, proposes that some people are biologically more emotionally sensitive from the start. Their nervous systems respond more quickly, more intensely, and may take longer to return to baseline. That in itself is not a flaw. It is a temperament. It is biology.  The same way their eyes are blue, or how intelligent they are, it is just how we are wired.  Difficulties become more likely when that sensitive system develops within environments that are invalidating, inconsistent, frightening, neglectful, chaotic, or traumatising.

Invalidation does not only mean obvious cruelty. It can mean being repeatedly told you are overreacting, being mocked for your feelings, being punished for distress, having your internal world misread, or only receiving care once your distress becomes extreme. It can also mean growing up in an environment where other people’s emotions were so overwhelming that there was little room for your own.

Transactional causation means that the person and environment affect each other over time. A highly sensitive child may express distress intensely. Caregivers may feel overwhelmed, reactive, helpless, critical, or inconsistent. That may make the child even more dysregulated. The child’s distress becomes bigger. The adult response becomes less steady. Over time, patterns form. The child does not learn enough about naming emotions, soothing them, trusting others, or asking for needs in safe ways. Survival strategies develop instead.

This is not about blaming parents, because some try really hard with great intentions, others don’t, and it is not about saying that there is one simple cause. Not everybody with BPD has a trauma history. Not everybody who experiences trauma develops BPD. It is usually a combination of emotional vulnerability, life experiences, relationships, and coping pathways.

Is BPD the same as trauma?

No, but there is significant overlap.

Many people with BPD have histories of trauma, neglect, abuse, attachment disruption, or chronic emotional invalidation. These experiences are strongly associated with borderline features, especially emotion dysregulation, mistrust, shame, fear of abandonment, and unstable relationships. At the same time, BPD is not reducible to trauma alone. Some people have significant borderline symptoms without a clear trauma history, and many trauma survivors do not develop BPD.  That is why the transactional and individual understanding is needed.

In practice, it is often more useful to think in terms of pathways rather than single causes. For one person, trauma may be central. For another, the strongest pathway may be emotional sensitivity plus chronic invalidation. For another, attachment disruption, neurodevelopmental differences, family dynamics, or long-standing shame may play the biggest role.

Autism, ADHD and BPD 

Neurodiversity and BPD can sometimes be mistaken for one another because, from the outside, they may share similar-looking features. Emotional intensity, rejection sensitivity, impulsivity, shutdowns, overwhelm, relationship difficulties, masking, burnout, and a strong response to perceived criticism can all be misread if we only look at behaviour rather than understanding what is driving it.

For some neurodivergent people, especially those who grew up undiagnosed, their differences may have been repeatedly misunderstood. A child who was overwhelmed may have been called dramatic. A child who struggled with transitions may have been seen as difficult. A child who was impulsive or emotionally reactive may have been labelled attention-seeking, rude, too sensitive, or badly behaved. Over time, this kind of invalidation can shape a person’s sense of self, their relationships, and their nervous system. They may learn to mask, people-please, expect rejection, or feel deep shame about needs they never had properly understood.

This does not mean autism or ADHD “cause” BPD, and it also does not mean that BPD is simply a misdiagnosis. For some people, one diagnosis fits best. For others, autism, ADHD and BPD may all be present. Neurodivergence can increase a person’s exposure to chronic misunderstanding, exclusion, bullying, sensory overwhelm, emotional invalidation, and relational trauma, especially in childhood. These experiences can contribute to the kinds of attachment wounds, emotional dysregulation and protective survival patterns often associated with BPD.

This is why careful assessment matters. We need to ask not only “What does this behaviour look like?” but “What has this person been trying to survive?” and “What support, understanding and accommodation were missing?” A compassionate formulation allows us to see the whole person, not just the label.

“Attention seeking” and “manipulative” are often harmful shortcuts

This is a part I feel strongly about.

When people use the phrase attention seeking, they are often describing distress that is visible, repeated, interpersonal, or hard for others to tolerate. But human beings are supposed to seek attention when distressed. That is how attachment works. That is how survival works.  Try switching the word attention for connection and you may understand more.

When somebody with BPD becomes highly distressed and signals that loudly, urgently, or repeatedly, what we are often seeing is not calculated performance. We are seeing a nervous system in alarm and a person whose ability to regulate privately has been overwhelmed. The behaviour may be the only available route to contact, relief, validation, or protection.

The same applies to the word manipulative. Some behaviours can absolutely have a powerful impact on other people, and that impact should not be minimised. Boundaries matter. Accountability matters. But impact is not the same as intent. A desperate threat during an abandonment crisis is not the same as cold, planned exploitation. Often these behaviours are maladaptive attempts to avoid unbearable emotional pain or disconnection.

None of this means “anything goes”. Compassion does not mean removing all responsibility. It means we are much more likely to help when we understand the function of behaviour instead of using contempt as a shortcut.

Why the diagnosis is so stigmatised

Part of the stigma comes from the fact that BPD often shows up in ways services find hard to hold. Repeated crises, self-harm, suicidal threats, rapid relational ruptures, intense anger, and dependency fears can evoke strong feelings in carers, loved ones, and professionals. If those reactions are not understood and reflected on, the person can quickly be labelled as “too much” or “impossible”.

Part of the stigma is also historical. The diagnosis has long been linked to stereotypes about difficult women, excessive emotion, and challenging patients. Research continues to show that people diagnosed with BPD often face prejudice, dismissal, and reduced empathy.

This is deeply unhelpful, because the evidence does not support the old myth that BPD is untreatable. Modern clinical guidance is clear that effective treatment exists and that many people improve substantially over time and I have seen that through my work.

What it might be like to live with or care for someone with BPD

Living with, loving, or caring for someone with Borderline Personality Disorder can be deeply meaningful, emotionally intense, and, at times, incredibly hard. It is rarely one simple story. There can be warmth, loyalty, humour, sensitivity, creativity, honesty, and a fierce capacity for connection. There can also be fear, exhaustion, conflict, confusion, and a feeling that you are constantly walking on eggshells.

People with BPD are often described only through the lens of crisis, conflict, or “difficult behaviour”, but that is far too narrow. Many people with BPD feel things very deeply. They may be highly intuitive, emotionally perceptive, passionate, loving, protective, and responsive to the feelings of others. When they feel safe and connected, they can bring enormous warmth, energy, and depth into relationships. They may notice tiny shifts in mood, remember details others miss, and care with real intensity.

At the same time, that same emotional intensity can make relationships feel frightening or unstable. For some people with BPD, the fear of being rejected, abandoned, misunderstood, criticised, or left can be overwhelming. A small change in tone, a delayed reply, a cancelled plan, or a facial expression that seems “off” may feel not just disappointing, but threatening. The person may react from a place of panic rather than proportion. To the person on the receiving end, this can feel sudden, confusing, or unfair.

This is where caring for someone with BPD can become emotionally demanding. You may love the person deeply and still feel drained. You may want to reassure them, but find that reassurance only works for a short time. You may try to say the right thing, only to feel that it has been taken the wrong way. You may feel pulled between compassion and self-protection. One moment you may feel incredibly close to them, and the next you may feel blamed, pushed away, tested, or shut out.

It is also common for loved ones to feel guilty. You might think, “If I was more patient, they wouldn’t feel this way,” or “If I really cared, I should be able to calm them down.” But one person cannot regulate another person’s entire nervous system. Support matters, love matters, stability matters, but you cannot be someone’s only coping strategy. Healthy care has to include boundaries, otherwise both people can end up overwhelmed.

The “bad” parts are not usually because the person is bad. They are often protective responses that developed around emotional pain, trauma, invalidation, attachment wounds, neurodivergence, or repeated experiences of not feeling safe in relationships. But understanding where a response comes from does not mean pretending it does not hurt. Compassion and accountability need to sit together. Someone’s distress may explain their behaviour, but it does not mean others should accept being shouted at, threatened, controlled, manipulated, repeatedly accused, or emotionally harmed.

For partners, family members, or friends, one of the hardest parts can be the unpredictability. You may start monitoring your words, your tone, your plans, and even your own needs. You might avoid saying no because you fear the reaction. You might stop sharing your own feelings because the other person’s feelings seem to take up all the space. Over time, this can lead to resentment, burnout, anxiety, or a loss of your own sense of self.

And yet, when things are going well, the relationship may feel deeply connected. There may be moments of tenderness, insight, laughter, affection, and emotional honesty that feel rare and precious. Many people with BPD work incredibly hard to understand themselves and reduce the impact of their distress on others. With the right treatment, skills, support, and relational safety, change is absolutely possible.

The key is not to frame the person with BPD as the problem, or the carer as the rescuer. The healthier question is: what does this relationship need in order to be safer for everyone?

That might include clearer boundaries, calmer communication, therapy, crisis planning, DBT skills, support for the family or partner, and an agreement that everyone’s feelings matter. It might mean learning not to respond to every emotional storm with urgency, while still staying kind. It might mean saying, “I love you and I am not leaving, but I will not continue this conversation while we are shouting.” It might mean offering reassurance without abandoning your own limits.

Caring for someone with BPD can ask a lot of the heart. It can require patience, emotional steadiness, education, and compassion. But it should not require losing yourself. The aim is not endless sacrifice. The aim is a relationship where pain is understood, responsibility is shared, and both people are allowed to feel safe, valued, and human.

How BPD is treated

The main treatment for BPD is psychotherapy. Current clinical guidance recommends structured psychotherapy that targets the core features of the disorder and is adapted to the person’s needs.

Dialectical Behaviour Therapy is the best-known approach, especially where there is chronic self-harm, suicidality, severe emotion dysregulation, or repeated crises. DBT combines acceptance and change. It teaches mindfulness, distress tolerance, emotion regulation, and interpersonal effectiveness. The goal is not simply to stop crises. It is to help the person build a life that feels more stable, meaningful, and worth living.

Other therapies can also help. Mentalization-Based Treatment focuses on helping people understand their own mind and the minds of others more accurately, especially when emotions run high. Schema therapy works with long-standing patterns and unmet needs. Other structured approaches may also be used. The key message from the evidence is that BPD can respond well to coherent, well-delivered psychotherapy.  But it’s important to highlight that structured DBT should be delivered in both group and individual therapy over a period of abut 18 months.  It is intense work, for an intense problem but at the end it is posssible for the person to no longer meet the criteria to have BPD.

Medication is not the main treatment for the core symptoms of BPD. Current guidance suggests that medication, if used, should be targeted, time-limited, and linked to specific symptoms or co-occurring conditions rather than treated as the primary solution.

Why I worked through an emotion regulation lens

In my own practice, I chose to work on the emotion regulation pathway with BPD because it fits both the evidence and the lived reality of what many people struggle with giving me a strong framework for understanding how emotions, attachment fears, self-harm, impulsivity, shame, and relationship patterns interact.

What I value about this approach is that it is both compassionate and practical. It validates the reality of the person’s pain while also helping them build skills, structure, awareness, and responsibility. It asks what function the behaviour serves, what vulnerabilities are in play, what is making the moment worse, and what could help right now.

That is often where meaningful change begins. Not in blaming somebody for being overwhelmed, but in helping them understand their patterns early enough to respond differently.

Can people recover?

Yes. Absolutely.

Recovery does not usually mean never feeling deeply again. It means feeling deeply without being repeatedly destroyed by it. It means recognising triggers earlier. It means having more tools when panic rises. It means being able to survive relationship ruptures without immediate crisis behaviour. It means building a steadier sense of self and a more stable life.

Clinical guidance remains clear that people with BPD can improve substantially with appropriate treatment. Many people experience reduced self-harm, less impulsivity, fewer crises, better relationships, and greater emotional stability over time.  I have seen this and I have been honoured to be part of it.

For anyone that does have a trauma background, learning skills to manage their emotions and relationships can then open the door for future therapy based on processing their trauma. Its a multi-layered approach that can really work.

A final note

BPD is a diagnosis that has often been surrounded by misunderstanding, judgement and stigma. But when we look beneath the label, we usually find a person who has been trying to survive overwhelming emotional pain, intense sensitivity to threat, and a deep fear of being rejected, abandoned or misunderstood. These responses are not signs of weakness or attention-seeking. They are often protective patterns that developed in response to invalidation, trauma, attachment disruption, neurodivergence, or years of feeling unsafe in relationships.

A more compassionate understanding of BPD does not mean ignoring the impact that intense emotions or impulsive behaviours can have. It means holding both truths at once: the distress is real, and change is possible. With the right support, people can learn to regulate their nervous system, understand their triggers, build safer relationships, reduce harmful coping strategies, and develop a steadier, kinder sense of self.

Therapy can help by providing a safe, consistent space to make sense of these patterns without shame. Approaches such as DBT, trauma-informed therapy, CBT, ACT, compassion-focused therapy and EMDR can help people develop practical skills for managing intense emotions, reducing self-destructive coping, understanding relational triggers, and processing painful experiences that may still feel active in the nervous system. Therapy is not about blaming the person or forcing them to “just calm down”. It is about helping them understand why their system reacts as it does, and gently building new ways of feeling safer, more grounded and more connected.

In my work as a Clinical Psychologist, I aim to look beyond labels and understand the whole person. This means exploring trauma, attachment, neurodivergence, emotional regulation, relationships, shame, coping strategies and the nervous system together, rather than reducing someone to a diagnosis. The goal is not simply to manage symptoms, but to help people develop insight, self-compassion, steadier relationships, and a life that feels less driven by fear and more guided by safety, choice and self-understanding.

As always until next time

Carla