Yes, his maladaptive behaviors (most of them) are probably caused by the drinking.
Now, understand it. Have understanding for the fact that he is doing what he is doing because he is sick. He needs help. And something people don't really think about is the fact that even though he is lying and manipulating you all the time, think about the lies and bs he is telling himself. I bet it's a thousand times worse.
That said, understanding does NOT denote condonement or acceptance of said behavior. If you are not alright with the behavior (which it seems you aren't) then you have every right to get away from him. You don't have to deal with it. Let him beat himself up a little more instead of you, maybe he will get tired of it and do something about it.
He may never get help. He may get help and relapse. No one knows.