I have no idea if you're crazy to be doing this for him.
I know that enabling alcoholics prolong their problem.
I also know that it's one helluvalot harder to detach from and stop enabling a child than it is a spouse.
I'm not judging you at all for putting him in a hotel. I would probably have done the same thing myself. Is it the most helpful thing for him? That, I'm not sure of. Maybe freezing and having to haul to a homeless shelter (where he won't be allowed if he shows up drunk) would be a good wakeup call. It's possible. But I also know I probably wouldn't have it in me to put one of my kids through that if I could avoid it.