Why am I attracted to abusive relationships?

My last two relationships have been abusive, but abusive in very different ways.

With ex number 1, it was more subtle - I got constant cristism and he'd say things which would offend me but of course I was oversensitive and being stupid as he was only joking. He used 'always' and 'never' a lot, for example in his mind I never appreciated him and I was always wrong apparently my feelings were wrong too. He namecalled, I was a bitch etc. He also didn't understand it was hurtful to namecall people I cared about, like my dad and my friends. He didn't seem to able to take any responsibility for his actions, everything was my fault and he continually painted himself as a victim. I felt like I was walking on eggshells the whole time.

With ex number 2 I got a bad feeling because when he was stressed he'd kick objects around, etc but he seemed perfectly stable at the beginning - then he had some severe psychiatric problems, it started with waking me up at 3am to tell me how fat I was and how disgusting I was for being so fat (I was 117 pounds...) he got counselling after that. But it wasn't enough, he was hallucinating and delusional, and during one of his delusional episodes started to strangle me. I stayed in the relationship thinking the person I had known for a couple of months was how he was when he was well. Rationalising it as you wouldn't leave someone because they were physically sick, so I thought it was wrong to leave someone who was mentally sick too. After eight weeks of treatment he seemed to be doing really well, and he was generally a brilliant boyfriend in that time frame... he was reliable, affectionate and supportive. However, he got into a fit of anger overnight, probabaly exam stress. We'd just had a really nice two days visiting his family together - he announced he was breaking up with me because he couldn't stand how fat I was for a second longer. I was shocked, it got really bad - I've been left with a few bruises and five partially dislocated ribs. I think the only reason why we broke up for good was because the commotion woke up his family, and his sister sent him a text with nasty comments so he's seemed to think I have disrespected his family by keeping them up (not accepting that he was keeping them up too) and he is too good for me like his sister told him (she has no idea what went on, and when his mum found me I presumed my chest pain was psychological from the stress of the situation, vomited a bit and got my friend to take me home.

After ex number 1, I thought I'd really built up my self confidence up, and I wouldn't let someone treat me disrespect me again but as you can see ex number 2 was worse!

I think I have a soft spot for mental health problems, as my brother has schizophrenia and my best friend has depression.

In fact I'd say my confidence before these two relationships, was above average for my gender (young woman are generally REALLY insecure) . Could my self confidence, be a challenge for abusers
Why am I attracted to abusive relationships?
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