What a story man. I don't think I would have been strong enough to stick around after all that. Your last statement really got me thinking. BPD has the highest suicide rate of any mental disorder. If I'm not mistaken it's 1 or 2 out of ten commit suicide.
My ex did mention she to tried to kill herself when she younger by taking a handful of pills. Seeing how much she lied, I only take what she says with a grain of salt. Heck, she lied to me in the beginning saying her liver was failing due to all the alcohol and pill abuse. Then a month later her liver magically healed and she started drinking again when she said shes done with alcohol. Didn't realize any of this till months after it was over, the fog cleared and I educated myself.
I witnessed how little emtions she shows to breakups with guys she supposedly loved or was going to marry. After she cheated on her man with me and left him, she went out with a friend the night she broke up with him, snorted coke, got wasted, cried a little, then the next day it was as if nothing happened. With me, her supposed "soulmate" the man she asked to marry 100 times, she cried in front of me a lot before she moved, then cried for hours before moving. Then the next day I spoke with her it was like I was her worst enemy, zero emtions. Now I know her tears weren't shed for losing me, but more about how I figured out her lies, tears of shame in themselves, how she failed again, not the person they supposedly loved.
They have that switch where they turn you off like you never existed. I can tell you this, if they were able to feel the pain they leave us in, there is no way they could survive it. It's that switch, coupled lack of empathy that keeps them going. They are survivors, my ex destroys every relationship, moves to another state, does it again, rinse and repeat all while blaming everyone but herself.
She lost almost everything after she destroyed our relationship. Racked up $6k in debt, lost 90% of all her belongings, even all her childhood stuff she collected. Moved 1000 miles back to her moms and started a new life like nothing happened. It is kind of amazing how they are able to keep on going after such tragic events. They are chameleons who adapt to any situation.