I guess I'm in the minority here, but just because he made jest of it, it's very possible he just really didn't take it seriously as it sounds like you were drinking buddies before. You told your other friend in person and he got it - maybe you should have had a face-to-face with your other friend and explained it to him in person as well instead of simply through texting. I think you may be surprised if he takes a whole new attitude to your 'no more drinking' if you were to let him know in person instead of second-hand through your other friend. I think it's worth one more shot to see if he's a true friend or not, in person. Obviously, if he still laughs you off, it's done.