Just eating when others eat to fit in

I have struggled a lot with dieting and never being happy in my body. Most recently I have been struggling with attending social functions or just going to a friend’s place and feeling like I have to eat because they do. I am trying to find the confidence to feel comfortable in social settings without having to eat.

Growing up I was told to take what is offered as a sign of respect. This is getting to me now more that that’s it’s summer and I keep getting invited places. Help!