Jaguar,
Alcohol does MAJOR damage to someone's brain. That includes the emotional and rational parts of the brain. You have to remember that he is very sick. But that does NOT mean you should tolerate the abuse. Abuse even by an out of control sick person is still damaging. If you live with him you should find some where else to live. If not, you should limit your contact with him. You should only be around him when he is calm.
Don't try to psycho-analyze him. Believe me, I tried it and it only lead to frustration. You will not be able to understand his actions or behavior.
