You just gotta tough it out until you get better and can cheat regularly. I hate to rub it in, but nowadays I just go for it if I want it really bad (I’ve been on diet for 2 years). This weekend I am going to a wedding and a BBQ with lots of poisons.
However, if you wanted to attend with them, I would find establishments that serve salads and other safe foods so that you can eat with them. Instead of desert, I would eat some fruit perhaps. Instead of the cocktails, drink some special tea. You can still make it special, you just have to think ahead.