Thanksgiving

I'm really really anxious about thanksgiving. I'm having two celebrations (divorced parents) and I know I'm going to binge, but I'm scared that I'll gain weight eating unhealthily for this week. I've wanted to purge today, but I can't bring myself to do it. I want to enjoy the holidays with my family, depression is making things hard enough without my eating disorder controlling me. Does anyone have tips on how to decrease my anxiety about this situation?