We are often set up on this path by our parents my mother was like that and I in most cases I chose partners that emulated either part or all of her worst behaviours. I am in most regards successful , independent and strong and immensely capable. Except in my personal relationships where I relived my childhood patterns ad nauseam. If I dissect the whys it is simple a part of me, a subconscious part, is trying to recreate the dynamics with other participants to maybe come out victorious for once -as the relationship to my mother will never resolve itself. But it is literal insanity because my partners like my mother were weak self serving cruel children who do not have the strength to fight their own demons so they rather make others miserable to feel better.
And even though i knew all this I always ended up in the same situation so I did the only thing I could do. I stopped dating. There will never be another relationship for me I am done. I rather focus on other things I am good at. Is it lonely, yes sometimes it is but it is so much better than the alternative.
RE: What it's like to be mentally abused - here is my take on it . My article called "You deserve it".