In my BPD article, "Salt to the Wound," I speak to the terrible pain we're in post-BPD relationship, and what exacerbates it. Ya know, it's hard enough losing someone we're bonded with, without endlessly analyzing what WE might have done differently, to have averted that loss.
People who have healthy self-worth never attach to Borderlines. They might meet em, they might go out with em a few times, but being connected with all their emotions and (thus) having their senses of instincts and intuition working FOR them, they sense it's dangerous to attach to that person, and so they don't.
People with poor self-worth are always hard on themselves. They shame and guilt themselves over past and current mistakes, they're super self-critical, and they have little respect or admiration for themselves (if any).
These are the folks who search their entire mental inventory, to try and determine what they 'might' have done wrong, to have brought this level of post-BPD relationship agony on themselves. It haunts them. It obsesses them. The degree of mental energy that's expended for MONTHS or even years over this shit, is astounding.
My piece, "Salt to the Wound" addresses why one STAYS trapped in pain after a BPD relationship. It is literally CAUSED BY questioning, shaming and beating-up on oneself, 24/7! So it's not bad enough, your ex made ya feel like shit~ YOU'VE felt compelled to clobber yourself with abuse, long after they're gone!
There is no greater pain, than that which we inflict upon ourselves, and this is one of the finest examples of self-flagellation there is. People with healthy self-esteem do not do this either, when a relationship ends. They may mourn and feel sad for awhile. They may at times miss the other's companionship . . . but they DO NOT beat themselves up for their relationship ending. That's the job of masochists (definition, people who thrive on pain).
As long as you're making this pain YOUR fault (ya know, like you've done since you were about 2 years old), you will never, ever be able to move beyond it. And the worst part is, you'll keep holding a torch for that ex of yours, wistfully hoping he or she will return to you one day~ or at the very least, being convinced you'll never love again.
All this mental masturbation incidentally, is designed to keep you out of FEELING the pain of loss in your body. When the mind is busy, it distracts from difficult emotions. In short, you are dissociating from feelings, rather than experiencing em~ which would help you finally put this terrible agony you're in, to rest.