Jarp - I am sorry this sucks. I went through it for a bit after RAH relapse. Here and there he mentioned having a drink. My only response was "its a bad idea but you do what you want". No discussions of alcoholism no nothing. He didn't drink my knowledge.
I think picking an argument over it is a manipulative way to do it, really saying it at all is. If they are going to why say it? Just do it. In my mind they want that fight because then the fight becomes the reason to. Best not to engage and you handled it well.
Time will tell, he may not.