Eat as little as possible. Do. Not. Binge before the day. The meal with kick-start your metabolism, convince your body it's out of starvation mode, and you'll actually lose like a pound. Drink lots of water, like, after every bite. Put your fork down after every bite. Spit out the food when you can, in a napkin or something. Take laxatives. Purge. Count your bites so you'll get bored eating eventually. Convince people you're sick. Convince people you have allergies/lactose intolerant/a vegan/vegetarian. Work out like a ***** before the meal. Fast for days before the meal. X
You're stronger than that! X
Just breath. Try not to over think it to much.
You'll just get more anxiety over it. Chat with family and just enjoy the company.
Don't worry. Having one day out of the year where you eat food in front of people isn't going to make you gain weight. Maybe a little water weight, but it will come off in a couple days. You could try to eat a bunch of diet jello to ruin your appetite ahead of time, if you're that worried you'll overeat.
Ummm..... Bulimia. But, really.... Just eat. It's not going to kill you, and it'll make your parents less worried.
thank you, captain obvious.
because there's not a more complex or simple way than that.