One of my uBPDw's big issues is that she can't handle sudden, stressful situations very well. These situations lead to her becoming extremely stressed out and moody for a long time, and if it's a particularly stressful situation she will keep getting worse until she dysregulates--even to the point where once she put a knife to her wrist.
This is a big issue for all pwBPD, not just your wife. As I understand it, what you describe is basically the core of the disorder - a lack of executive control over relatively normal emotional responses to stressful situations. I've seen my wife go through this over and over. It may be an "everyday life" type of trigger - someone cuts her off in traffic, a friend does not call her back, or a boss at work telling her to do something different. And she stews and lives in her head until it winds and spins into a tornado that finds its way out somehow. Everything and anything could be a source of stress for my wife, including things such as having to choose what she wants for dinner.
At least part of the issue is anxiety. Anxiety is part of the normal human condition, but with pwBPD, anxiety seems to be debilitating, as if it reaches some kind of threshold in which the anxiety itself breeds more anxiety. I don't think anxiety is the only issue at play here - depression, and especially shame play major roles in the dysregulation. As a typical example, my wife may be feeling anxious about a job interview. That's normal; we all feel anxious. But combined with that is her shame of *years* of failure at jobs, and depression that leads so a low self image and a pessimist attitude toward life. So, she is naturally anxious, but combined with the other emotions, it's just an unstoppable storm. The end result is that rather than take ownership of her emotions, her emotions are blamed on others.
My wife has taken all kinds of medicine over the years, and just yesterday she revealed to me the only ones that have really helped her are the Bezos (Xanax) that are short acting against anxiety. I don't think she claims they solved her problems, but I think the Xanax takes her from the "low functioning" category to the "functioning" category. The core BPD issues still remain (fear of abandonment, splitting, low self esteem), but the crippling anxiety is lessened so that things like job interviews and going to the store don't set her off. Let's put it this way - on Xanax she was able to live internationally for 4 years, by herself and travel by herself. Off of Xanax, she struggles to even go to the store without me. The reason she does not take Xanax now is because she is a former Heroin abuser, and Xanax can be very habit forming, and she also has concerns about long term side effects and hazards if she were to get pregnant.
My feeling is that the best medicines to help lessen dysregulations would probably be benzos for anxiety. They won't cure the BPD, and should be approached with caution for a pwBPD, especially if they have had other addiction issues.
