I get the feeling that alot of people take the holidays as some magical time that isn't reality. False! People love excuses. An excuse like, "I can't [fill in any activity] because it's the holidays" is bullshit. "Can't" or "won't?" is my question.
I think most commonly this is in reference to dieting. Now, I'm not saying that the holiday season should be some time of atonement and deprivation, a stand-off between your will power and the tray of desserts staring back at you. What I am saying is that with some discipline and motivation, a person can make it through the holidays without completely fucking up his or her goal-oriented plan. (On a side note, if you are doing something, anything, you need to set goals. Here is a great place to start learning about goal-setting: http://www.t-nation.com/free_online_article/most_recent/5_surefire_steps_to_setting_goals&cr= ).
Motivation is easy, and motivating coaches are a dime a dozen. Discipline is much harder. I cannot give you some magical plan that will keep you disciplined. I believe you need to find that discipline within yourself. You have to know that achieving your goals is much more important than eating yourself into a coma during the holidays. Interestingly enough, with a good plan, you could even schedule in a cheat meal or cheat day during the holidays, thus taking off a little mental pressure.
To switch gears, I'm going to address the skinny bastards out there. The holidays are your time to really sac-up. Mom's on a diet? Sister is too? GOOD! Eat their portions! It's not cool to be small and weak. I think there are dozens of reasons why society has shifted in the last 15 years and wants men to be 150lbs and androgenous, but that's beyond the scope of this article. The fact remains, you NEED to gain weight. If you're going to play a sport, fight somebody, or take care of your family, you better be big AND strong. So don't you dare let anyone else take the leftovers. They are yours to be consumed completely. You have a just-as-skinny-and-weak brother that wants those leftovers? Fight him for them. That's natural selection right there. Somebody is getting that food, and it better be you. Worried about losing your abs? Who cares! Are you going swimming is January? Doubtful. And even if you were, huge traps and tree-trunk legs are much more awesome and intimidating than 4 abs and no muscle.
Finally, if you think that the craziness of the holidays has to effect your training, you're dead wrong. I'm not telling a parent to prioritize a bench workout over seeing his or her kids (maybe a squat workout though); what I am saying is that you can get your shit done no matter what. Unless 3 family deaths, a tsunami, and a blizzard all strike at once, I think there's enough time in the day/week to get your work in, even if it's abbreviated. Plus, with all the extra food you should be consuming, the BLOAT will be epic and your numbers should go up nicely!