It would suck for me to not take at least some bites of these favorite dishes. I would guess that if I didn't actually taste some of them, I would rebound like a high school girl after a breakup and eat like a pig at home. Later. Maybe at midnight, alone in the kitchen. No kidding. My advice is to eat the salad as planned, take a spoon (not the big spoon) and get one spoonful of 5 of your favorite dishes. Then choose one that you get to have a second spoonful. After that, go where the little kids are and play with them to keep yourself busy. If you get hungry, get more of that salad you brought. This is what the holidays will feel like. Good luck!

So, I have 3 rules for get togethers.
1) 99% of the unhealthy food there is something you've had before (or relatively close) so you already know what it will taste like. Don't bother eating it. It's pointless. It's not some strange exotic new dish you've never heard of.
2) Find someone who is empathetic to your situation and Brag about how good you're doing and trying to be. I find that once you announce the changes your making and what your goal is, you kind of force yourself to be accountable.
3) If it's staring at you, screaming at you to taste it... then I ask someone else to get me 1 forkful. No plate. Plate = obligation to finish. A fork is legitimately a taste.