BPD Mood Swings: Understanding Emotional Highs & Lows

Rapid Mood Changes and Emotional Instability

Affective instability in BPD means that the mood shifts are:

• Quick.
• Strong.
• Set off by something specific.

Often, it’s an interpersonal trigger, such as feeling let down, slighted, or rejected. That’s what makes BPD’s version of mood swings distinct from everyday moodiness.^[1]

BPD mood swings can move in both directions as well. Your mood can lift suddenly. Then it can drop just as fast, a little while later. When you have BPD, these highs and lows tend to be bigger than they are for other people.^[2]

These intense emotional states usually last a few hours, but sometimes, they might last multiple days. In many cases, an ordinary day can involve multiple changes in mood.^[3]

Why “Mood Swings” Doesn’t Tell the Whole Story

Using “mood swings” to describe the emotional experience of BPD isn’t quite accurate. It tends to carry a stereotype of a lack of control, that perhaps someone is just “being moody” or “too sensitive.”

The reality is that BPD involves reactive instability, not a personality characteristic or perceived flaw. The label “mood swings” can make it sound like you’re choosing to be difficult. But your emotional system is reacting intensely to things that matter to you, especially relationships.

Emotional Sensitivity and Emotional Dysregulation

Emotional dysregulation usually works in a sequence, and it usually starts early. You feel things more easily and more strongly than others seem to. Those feelings rise fast. And because the tools for calming those emotions were never fully developed, you end up reaching for whatever brings quick relief, even when it doesn’t help for long.^[4]

This isn’t a character flaw. The emotional regulation skills that other people developed early, often without realising it, may not have developed in the same way for you. That’s not your fault.^[4]

People with BPD often use ineffective coping strategies to deal with their emotions. For example, you might replay an upsetting moment over and over in your mind to try to resolve it. While this strategy might feel like it helps in the short term, it doesn’t help resolve the unsettled feelings in the long term. In fact, it keeps those feelings alive and intensifies them, rather than settling them.

As another example, you might try to suppress the feeling to make it stop. But, again, while you might experience some initial relief, this isn’t an effective strategy because it tends to make that feeling stronger. Suppression works for a few minutes, then the feeling comes back, often more intensely than before.

During an emotional surge, it can be genuinely difficult to name what you’re feeling. You might not even be able to separate what you’re feeling from other emotions: hurt from anger from fear, for example.^[4] That in and of itself makes it hard to navigate the emotional experience. When you can’t name what you’re feeling, it’s more difficult to respond to it effectively.

How Early Experiences Shape Emotional Instability

Borderline personality disorder usually develops where an intense emotional temperament meets an environment where you can’t make sense of or soothe big feelings. How your emotions work today reflects how those parts of you developed, not because of a failure of effort on your part.^[4]

If the adults around you growing up couldn’t help you regulate your emotions, or dismissed or punished your emotional responses, you didn’t get the chance to develop emotional management skills.

Like any mental health condition, BPD isn’t caused by a single factor. Genes and difficult early experiences interact with one another. Some research suggests that BPD might result, in part, from how emotion and control circuits work in the brain. However, there isn’t a settled, proven brain model of BPD.^[1] What we know is that biology and environment both contribute.

Therapies That Ease Emotional Dysregulation

Psychotherapy isn’t just one type of intervention. Numerous forms of psychotherapy are well-supported for treating borderline personality disorder:^[1][6]

• Dialectical behavior therapy (DBT) helps build skills for managing intense emotions and relationships.
• Mentalization-based therapy (MBT) is effective in helping you understand your feelings and the feelings of others.
• Transference-focused psychotherapy (TFP) focuses on working through relationship patterns in the context of the therapeutic relationship with your therapist.
• Schema therapy assists in reshaping long-standing emotional patterns.

All of these therapies are well-researched. None are superior. Having options means you can get tailored treatment for your specific situation. It also means that if one doesn’t feel right, other research-backed options are available.

Name the Feeling

One thing that can help is to focus on naming your feelings and separating them from other feelings as they arise.^[4][6] When you feel an emotional change occurring:

• Take a purposeful break.
• Take a deep breath.
• Focus on what you’re feeling. Is it hurt? Anger? Fear? Shame?

Naming the emotion, even silently, can reduce its intensity.

Ride the Emotional Wave

Another useful skill is to act based on the fact that the emotional wave is often short-lived. Rather than trying to fix the feeling or stopping it altogether (neither of which provides long-term relief), try focusing on getting through the feeling without doing something that creates a new problem.^[3][4]

For example, someone with BPD might interpret a friend canceling plans as a slight that triggers a fear of abandonment (a hallmark symptom of BPD). This, in turn, can cause an immediate downturn in mood and an urge to withdraw.

Riding the emotional wave helps protect against this. Recognizing that the worst of the emotional intensity is temporary (even when it doesn’t feel like it in the moment) allows you to focus on how to move forward. Once your mood stabilizes, you can think about the triggering situation with a clearer mind.

Putting a gap between the emotional surge and the impulsive action often means the impulsive action doesn’t take place. Just sitting with the emotion helps steady things. It builds distress tolerance; you learn that heavy or painful emotions are part of the experience, and that reacting to them immediately might do more harm than good.^[3][4]

Develop a Routine and Focus on Relationships

Having even a small amount of routine can help, too. When you’re sleep-deprived or your days are chaotic, your emotional system has less capacity to handle stress. Things like steady sleep and predictability in your daily routine can help keep your system from running on empty. This can help make big feelings a little more manageable when they come up.^[6]

Since BPD centers on interpersonal sensitivity, having meaningful connections with others can also be helpful. Supportive, stable relationships can help stabilize you when an emotional wave hits, and are a counterweight to the rejection sensitivity that drives the emotional reactivity of BPD.^[6]

Each of these techniques can help prevent a hard moment from becoming a more harmful consequence. But none of this is meant to be done alone, and lasting change, the kind that makes the emotional waves smaller and less frequent, often comes from working with people who understand what these moods are and how to steady them.