I would say find a friend or romantic partner that makes the holidays more enjoyable for you. That worked for me.
That way you either have somewhere else to go so you don't have to spend the whole day with family, or you can invite your friend over to spend time with you and your family. Unless your family are just a bunch of total heathens, the guest of your choice should act like a buffer.
I'm still not a fan of the holidays, but since I have my bf, my family doesn't pick on me so bad and I don't end up in the other room crying.

Thanks. Yeah, my goal is not let them make me cry...again.

ST- Bless you Sweetie. I'm sending you a PM, ok?

Going through the same thing. I think it's even harder at Christmas because everyone talks about it being the most wonderful time of the year. I love Christmas and go all out, decorating, baking, etc. But lots of times I just have this underlying sadness.
I'm sure part of the problem is the dark. I have S.A.D. and live in the northeast. We get about a day of sunshine every week. Today it is sunny so I went outside in the cold just to let the sun shine on my face. It helped.
Over the past couple years I have been trying to be proactive and prepare myself. I have been buying and reading books about the true meaning of Christmas. This year I am reading "Hidden Christmas" by Timothy Keller. It has been really helpful. It seems that when I am reading and focusing on something like that, the depression lifts.

My parent are medical doctors. They do not understand my sytomos.

Finding a friend to bring with always reeeaaally helped me. Otherwise I would typically read or knit in a corner and keep my head down. Talk when I had to and be pleasant, but just kinda hang in the back. Go to the bathroom for breaks from everyone. And just try to kind of meditate into your own head. Focus on breathing (can send you links to breath work if you'd like).
Something I would always do too, in regards to ED, was to get small portions of food on big plates, eat slowly, and get seconds to munch on. Nibble little bits all the time. It will appear as if you are eating a lot more than you really are.

I don't know if any of these things are viable options for you but maybe they sparked some ideas of your own!!

Thanks for the suggestions!