Borderline Disorder Mood Swings Explained

By Randi Kreger, author of Stop Walking on Eggshells: Taking Your Life Back When Someone You Care About Has Borderline Personality Disorder and The Essential Family Guide to Borderline Personality Disorder: New Tools and Techniques to Stop Walking on Eggshells.

Just like people with diabetes have problems regulating their blood sugar, folks with Borderline Disorder have difficulty regulating their emotions. These out-of-control feelings fuel actions that impact every part of a borderline person’s life, especially their interpersonal relationships.

Although people with Borderline Disorder feel the same emotions everyone does, there are some differences. One big one is that mood shifts are frequent and unpredictable, as you’ll see with the following example of Rachel. She is based on a real-life person and situation.

Rachel’s Dilemma

Rachel, a young woman with Borderline Disorder, wants to leave her boyfriend, Ryan. It’s 2 a.m. and she’s angry, and she can’t wait to tell him in person. So she writes him an angry text informing him they are no longer together. She suggests they set up a time to exchange “stuff.”

An hour later, she’s online and sees that his favorite band is going to be in town. She gets excited because she knows someone who works at the venue, and texts him that maybe they can go together and there’s a chance her friend Shelly can get them backstage.

That makes her smile. But it also reminds her of the first concert of the band they attended, when he called his ex-girlfriend in the middle of one of their best songs and held up the phone for her to hear. She feels almost as bad as she did that night—the ache of betrayal, the sting of jealousy, and the whole night was shot.

She texts him once again to remind him what she thought of that. Ten minutes of explaining why the breakup is so justified improves her mood.

But 15 minutes later, she regrets her actions when in a rush she remembers just how profusely he apologized after the fight that ended up in them both screaming and crying. He truly didn’t know how awful that would appear to her. In the end, it brought them both closer, and the night ended with sweet kisses and promises of forever.

This makes her weep and regret everything. Why did she write that last text? She needs to call him now to tell him not to read that text. She calls—no answer. She runs to get a tissue to blow her nose and sits down to write an apology text.

When Ryan checks his phone the next morning, he has nine texts from Rachel. The ninth one tells him to ignore the previous eight and that they should sit down and talk.

Help for Mood Swings

Dialectical Behavior Therapy has a skills training module called distress tolerance that helps people sit with painful feelings instead of acting on them in ways that cause problems later. Had Rachel used distress tolerance skills (see links below), this situation may have been avoided. Medications also target depression and mood swings.

Further Resources

Distress Tolerance Skills for BPD VeryWell Mind by Kristalyn Salters Pedneault

DBT Handouts & Worksheets

The views and opinions expressed on the Black Sheep Blog are those of the author and do not necessarily reflect the position or policy of the Black Sheep Project or its employees. The Black Sheep Project is not responsible and does not verify for accuracy any of the information contained in the stories shared here.