Well, yes, that could be part of it. The used to it bit, not the stupid! You know the story of the frog? Put it in boiling water and it will jump straight out. Put it in cold water and heat it slowly on the stove and it will stay in and die.
I haven't been here in a while, so I'll have to go back and read your previous posts, but is the drinking actually the issue? Is he otherwise kind and supportive and an asset (rather than a hindrance) to your life?