What Rock said. He sounds like trouble on any number or levels, narcissistic, sociopath, a bit of both. I am sure you know this, but you dodged a bullet and stopped drinking too, double blessing.
Sounds like one of the things you feel bad about is being back with your parents. You don't say your relationship with them, but my brother lived with my mom from about 30-50 when she died. She loved having him and being able to help him and he her.
Not suggesting you should make this a permanent solution, but there could be another blessing in there somewhere.
Main thing is to realise it is him, not you. Dont blame yourself, forgive yourself, and you will meet someone worthy.
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