Everyone is different, but I can say that I felt very much resonation with your post and your experience.
My exRAH was so mean. I would record him so I coulr relisten to be sure he meant it, or whatever...Maybe to help me make the choice to finally leave.
We have a 7 year old son.
RAexH got sober 2 years ago.
He is still mentally ill.
I thought he acted the way he did because he was drunk.
He was mentally ill. and he still is.
He is an abusive and broken person.
He did not seek the mental health support that I required as a condition of him coming to live with us.
I now see that he does not want to be mean when he is. and when he was drunk he was just miserable. I think he has no other skills. He is angry and beset and cruel as a result.
He is more reasonable about money, can hold a job, can father our son, but he cannot MAINTAIN normal behavior in an intimate relationship/
I have come to believe that he suffers from a true Personality Disorder.
I am sorry to say this, but you may need to not ask your self WHY he does what he does, but rather to take his reasoning and justification out of the picture and just look at the result: You and your daughter being visciously emotionally and mentally belittled and abused.
Is there any good reason or justification for that?