Originally Posted by
nodaybut2day 
If I examine myself honestly, I think I'm ok with people having a few drinks at dinner, and I'd be alright with having a cocktail myself once in a blue moon, but I have no interest in cavorting around town drunk (which I used to do a lot in my university days). There's simply no room/desire in my life for that kind of stuff anymore.
I'd say that's an excellent summary and the basis for a good, solid boundary. Bear in mind that boundaries aren't about one other person's behaviour - they're about our own behaviour. I'm much the same as you now. I find that I am comfortable being around people who have had a couple of drinks but not around people who are noticeably drunk. I'm not sure I could articulate where that line exactly is apart from "If I start to feel uncomfortable, the line's been crossed." And I think that's ok. I'm not even attempting to stop anyone from drinking, it's just that once I start to feel uncomfortable then I'll make my polite excuses and leave.
That is important for me because when I was with my AXGF there were hundreds of times where she'd be drunk, I'd be excrutiatingly uncomfortable about the situation, I'd know it was just going to get worse, but I'd stay there out of some misguided sense of loyalty. I know better now.