There's lots of reasons, alybally. Part of it is shame. Alcoholics are often deeply ashamed of their drinking on some level, and they sabotage relationships because they don't feel worth. Another reason is pride. They lose control and lose power in a relationship which is threatening to them. This causes them to lash out.
Of course another big issue is that drunks just don't generally make good decisions. Being plastered all the time doesn't help your mind make rational decisions.
I'm sorry you're dealing with this, alybally. Maybe Al-Anon would be a good idea. Obviously I don't know you at all but I do know you don't deserve this treatment- no one does.
