If you or someone you care about has Borderline Personality Disorder (BPD), you’ll know how complex it can feel. BPD isn’t a one-size-fits-all diagnosis. In fact, there are different subtypes of BPD – four of them, to be exact – and each has its own traits and behaviours.
Understanding these subtypes can make a real difference. It can help you make sense of your experiences, or better support a loved one. So, let’s take a look at what these subtypes are and how they show up.
Table of Contents:
First, a quick word on BPD itself
Borderline Personality Disorder is a mental health condition that affects how a person thinks and feels about themselves and others. People with BPD often struggle with relationships, emotions and self-image. It can feel intense, confusing and at times overwhelming.
But not everyone with BPD experiences it in the same way. That’s where the subtypes come in.
The four subtypes of BPD
The subtypes of BPD were first introduced by Dr Theodore Millon, a psychologist who studied personality disorders in detail. He suggested that while all people with BPD share certain core traits – like emotional sensitivity and fear of abandonment – they may express those traits differently.
Here are the four subtypes:
- The Discouraged Subtype
- The Impulsive Subtype
- The Petulant Subtype
- The Self-Destructive Subtype
Let’s break down what each one means.
The discouraged subtype
People with the discouraged subtype tend to hold their feelings in. They may seem shy, quiet or overly dependent on others. Underneath, they often carry deep fears of being abandoned or rejected, but instead of expressing those fears outwardly, they turn inward.
Key traits:
- People-pleasing and eager to gain approval
- Often struggle with low self-esteem
- Can feel helpless, hopeless or stuck
- Tend to rely heavily on others for emotional support
- Might hide their distress to avoid being a “burden”
This subtype can sometimes look like social anxiety or even depression. People with the discouraged subtype might seem calm on the outside, but inside, they can be battling intense emotional pain.
In relationships:
They may cling to people out of fear of being alone, but avoid speaking up for themselves. They worry that showing anger or neediness will push others away.
Support tips:
- Encourage open communication
- Reassure them that it’s okay to express feelings
- Help them build confidence in their own decisions
The impulsive subtype
The impulsive subtype is just what it sounds like – fast-moving, energetic and often unpredictable. People in this group may act on urges without thinking them through. They crave excitement and may struggle with boredom or emptiness.
Key traits:
- Risk-taking or thrill-seeking behaviour
- May act without thinking through consequences
- Fluctuating moods and difficulty staying still
- Can appear charming and outgoing at times
- Prone to sudden changes in relationships or decisions
This subtype can overlap with other conditions like ADHD or bipolar disorder, so it’s sometimes hard to spot. But the impulsivity is often rooted in a deep need for validation or connection.
In relationships:
They may jump into relationships quickly, then pull away just as fast. The fear of abandonment is still there, but it’s often hidden behind fun-loving or rebellious behaviour.
Support tips:
- Offer grounding tools for managing impulsive urges
- Create safe routines that support stability
- Be patient – changes take time
The petulant subtype
The petulant subtype tends to be more emotionally reactive. People in this group often feel angry, moody or frustrated – and they may not always know why. They want connection, but often feel let down by others.
Key traits:
- Irritability, mood swings or sudden outbursts
- Struggles with trust – may push people away before they get hurt
- Passive-aggressive or controlling behaviours
- Can feel unloved even in close relationships
- Often feels let down, misunderstood or unimportant
This subtype can be tough – both for the person experiencing it and those around them. The emotional intensity can lead to arguments or misunderstandings, even when the person doesn’t mean harm.
In relationships:
People with this subtype may test boundaries or create conflict to see who will stick around. There’s often a deep sense of “I’m not good enough” underneath.
Support tips:
- Validate feelings, even during tough moments
- Set kind but firm boundaries
- Encourage therapy focused on emotional regulation
The self-destructive subtype
The self-destructive subtype is often the most visibly intense. People in this group may turn their emotional pain inward – through self-harm, risky behaviour or other forms of self-sabotage.
Key traits:
- Engages in harmful behaviours (e.g., self-harm, substance use)
- May push away those who care most
- Feelings of emptiness, guilt or shame
- Often says or believes they “don’t deserve” help or love
- May experience suicidal thoughts or actions
This subtype is a cry for help – not attention, but real support. The person may not believe they’re worthy of love or care, and that belief can lead to dangerous choices.
In relationships:
They may seem to reject support, but often it’s because they fear being a burden or believe they’re beyond saving. Underneath is a longing for connection – just with layers of pain in the way.
Support tips:
- Take signs of distress seriously
- Encourage professional mental health support
- Offer consistency, even if they push back
Can someone have more than one subtype?
Yes – absolutely. These subtypes aren’t boxes that people stay in. Many people with BPD experience traits from more than one subtype, or move between them over time. They’re more like themes than fixed categories.
Also, not every mental health professional uses these subtypes in diagnosis. But they can still be useful for self-understanding, therapy or simply putting feelings into words.
Why do the subtypes matter?
When you understand how BPD shows up differently in different people, it becomes easier to respond with empathy – whether it’s towards yourself or someone you love. Subtypes offer a more personal look at what’s going on behind the behaviours.
They’re also helpful in therapy. Knowing your subtype (or combination of subtypes) can help tailor the kind of support or treatment that works best for you.
How to get help or learn more
If anything in this article sounds familiar, know that you’re not alone – and that help is available. You don’t have to fit a perfect picture to get support. BPD is treatable, and people recover with the right help.
Here are some resources where you can learn more:
- Mind (UK): https://www.mind.org.uk – Mental health charity with guides on BPD and therapies
- NHS Personality Disorders Info: https://www.nhs.uk/mental-health/conditions/borderline-personality-disorder/
- Books to consider:
- Stop Walking on Eggshells by Mason & Kreger
- I Hate You—Don’t Leave Me by Kreisman & Straus
Final thoughts: The four BPD subtypes
There’s no single way to experience BPD. These four subtypes – discouraged, impulsive, petulant and self-destructive – give us a lens to better understand the complex ways BPD can affect people.
If you’re on your own journey with BPD or supporting someone who is, know that every step toward understanding counts. And you’re doing a good job, just by learning more.
