I like Colette's suggestion about keeping workouts on track, and sort of going with the flow in terms of eating at this time of year. Yesterday's workout for me was running:
1335 feet ascent
1274 feet descent
The run was tougher than usual because I'd done a heavy leg workout the day before. But the run needed to happen when it did, because tomorrow we're heading up the hill for snowboarding (our THIRD trip this season!), and I want fresh legs. It's been raining here all week, the snow should be sensational and I can't wait!
Here's a post that talks about having an anchor for your eating. It's written for when you travel, but works very nicely in the context of holiday craziness. (I'm writing this as I finish my everyday breakfast bowl of oatmeal/flaxseed/Splenda.)