That's where I quit counting calories and go with diabetic exchanges or plate method. Get a workout in before I go. Then relax and let it go. It's a celebration -- and we seek balance in life.
8 potluck thingies a year is nothing to wig over. That 8 meals out of what? 3 x 356 days - 1069? It represents 0.7 % of the eating opportunities I face yearly. Being a wee bit more relaxed isn't gonna kill me or ruin my plan. It isn't even 1%!
I don't need to know the recipe to know 1/2 cup cooked vegetables is 1/2 cup cooked vegetables. I know that the recipe's calorie load will not be exactly as light as nekkied steamed veggies, but it's only 1/2 cup so... I also know it can't be 5 zillion calories either!
At our solstice potluck thingie I plan to bring some on plan foods and just taste the best 2 or 3 of the others. I don't NEED to taste them ALL -- there's always the next one coming after. It's not like we run OUT of of spokes on the wheel of the year. YKWIM?
Again -- walking the line of balance. Celebrate but not overdo, but do celebrate. Not underappreciate the wonderful gifts given.