We did the wedding thing this weekend, also. I ate completely OP (actually gave DH instructions ahead of time that I was to eat no bread, no sauces on anything and no potato but I would have dessert and should he seeming me indulging, he was to say something). Sooo, having decided to have dessert, I did indulge in 3 small desserts, but that was all. I enjoyed them while I had them, but knew that I would need to get back on track on Sunday. When I weighed on Monday morning, I was down an extra pound over the weekend.
I find that I can indulge in a few odd treats and still stay on track with the eating program ...provided I plan the detour into the off program foods before I get there. I also find that, if I say I am going to stay strictly OP when I am at events like that, the temptations are too great when I get there, that I tend to binge eat, have guilt feelings afterwards along with difficulty getting back on the program.
Sometimes the plan to be bad is better than trying to be good all the time.