Fast afterward
If you are going to cut back on eating to compensate for going to a party, do not fast that day. Do not go to a party starving. Fast the next day when you are full.
Plan ahead
If you know you are going to a party where they will have made something that is your favorite, concentrate on eating that.
Keep it festive
Stay with the holiday foods that make the season special. You do not need to eat the same old cheese and crackers, chips and pretzels.
Maybe once a week
Dessert for lunch! Not lunch plus dessert, but just the dessert you are craving. You should do this at most once per week (and preferably less) but this will allow you to not feel deprived and the calories will count as a meal.
Be more active
Increase physical activity. If you are going to eat more, exercise more. For example, while you are shopping park as far from the store as you can and bring your packages back to the car periodically.