What stuck out to me was "emotionally stable" and "BPD traits" in the same sentence, there's no such fvcking thing. If she was emotionally stable she would not flip between needing you and rejecting you, it's a roller coaster needs, when down and ignores when up. How is that stable? It's going from one extreme to the opposite without any balance or at least moderated normal fluctuations. I can certainly understand your dad just going mentally offline, dealing with such an unstable personality is very stressful.
Onto me now. My mother is a vulnerable narcissist, point at any flaw and you start world war 3. My father ditched her when I was 2 years old, shortly after he found my step-mother. They've been married for almost 20 years, still going strong together. I lived some of my time with my mother, but after the age of 10 I lived with my father and step-mother until I moved out at 19. Used to sleep at my mothers apartment every other weekend, went fine until about the age of 14. That's when I found out she smoked weed, there was a lot of fighting between her and her boyfriend at that time until they broke up for the last time. I witnessed her physically threatening suicide, he strangling her, they using amphetamine and other drugs. I will never forget her sitting with a knife to her throat, that happened once and on my way to recovery I spent 2 months in extreme depression trying to deal with that one memory.
If that wasn't bad enough it got worse when he finally after 10 years of abuse packed his sh!t and left, this was 3-4 years ago I believe. What happened then was that she shifted her focus onto me, I was practically the only person left in her life. She called and I did sh!t for her all the time, buy groceries because she was "too sick", pick up her medication (strong pain killers, way more than she needed, clearly abuse and addiction) and her doctor didn't have enough balls to stand up to her. If I just even hinted at not doing what she wanted I faced guilt trips, shaming tactics, suicide threats, death threats and extreme rage being called pretty much the nastiest things you can imagine hearing. If I didn't do what she wanted I was a worthless piece of sh!t that didn't deserve the light of day, that was pretty much the most emotionally damaging thing I have ever experienced.
Being exposed to all that sh!t and eventually being the main target made me the world's biggest doormat and people pleaser. I jumped whenever someone wanted me to jump out of pure fear for my life. I feared people to death, I was having trouble with even taking an innocent phone call to something as simple as customer service. I was alone, fearful, desperate and the only places I felt safe was home, with the few friends I had left and at work. This is why I was a nice guy, I expected everyone to be as cruel as my mother.
My father and step-mother always supported me and they love me like there's no tomorrow, they have fought for years trying to keep me on a good path. When I moved out they couldn't watch over me anymore, so I became isolated and fearful, when I was home they paid attention and noticed when something was off. On my recovery I realized how much they care and how little my mother cares, in fact I place far more value on my step-mother than my biological mother. My relationship role model is my father and step-mother, they've gone through so much sh!t and they never gave up on each other. Today this is paying off for both of them, they're just pure awesome.
What they're doing is working and has worked for about 20 years now, there's no indication of it ending until they're dead. As for my mother I told her to fvck off and went NC. I won back my confidence, my self-respect, my feelings, my co-workers respect, my creativity, my will to live and fvcking love it.
tl;dr My mother is a fvcked up narcissist, my father and step-mother are awesome and my upbringing was mostly very good with a few too many extremely negative events. I feel successful now and there's more to come.