"Is it worth it?"
Coworkers have heard me ask this a time or two over the past few years. Its a test I use routinely to evaluate whether or not to indulge my sweet tooth.
I have one of those. I am convinced I physically need a little small something sweet each day, and while I am very careful about the size of said indulgence, I don't neglect my craving. However, I do budget accordingly and I am very strict about what it is and how much. It might be just one small hersey kiss, it might be a small glass of chocolate milk after a run (sometimes its the only bargaining tool to get my out the door on my runs when the weather is crappy!!!).
Anyway, the point is, a holiday is A DAY. one day. Not lots of days, not a month, its one day. While you probably won't gain a 10lbs that day, you also don't want to sabotage your hard work. So choose what you indulge in by priority and judge wether or not its worth it.
For example, I love pumpkin pie (see? quite the sweet tooth!). I don't really care about mashed potatoes, stuffing, or anything else. So I'll eat my veggies (we usually have tons of veggie sides since my mom and I don't eat meat) and pass on huge helpings of mashed potatoes since I know I'll be having pumpkin pie later. If I was at a holiday party, I'd make sure I wasn't starving before I go, and then pick the things that I would want the most. Don't like cookies as much as you love bacon wrapped dates, well then keep your hands off the cookie plate!!
Prioritize what it is you look forward to most, cut back where you won't miss it, and make sure the calories are worth all the extra workouts you'll need to do!! :)