Hi One23. While I'm not an alcoholic (not sure why I always feel I need to make that disclaimer but I do lol) as I was reading your post I was thinking - boundaries, which you then mentioned.
There is a book that is often recommended in the Friends and Family forum here - Codependent no more - by Melody Beattie. You might find it helpful. To be sure I am not implying you are codependent or not, I don't know you! Just that there is a lot of good information in there about relationship dynamics and boundaries, that you might find useful.