I used to get angry that I couldn't just go out and have a drink. But it never ended very well when I did. I still get wistful at times but it's usually fleeting.
It does get easier but I still avoid get togethers which are about the alcohol. I'm skipping a retirement party as I type this. "Oh, I am sorry but I can't. I have to pick up my kids at the sitter."
Sounds like this friend is pretty insecure about your choice and is deliberately obtuse. Time to take a break while you find your footing.