What should I do now?

I suffer from really bad anxiety and depression I think now. I also have body dismorpah and an eating disorder. My boyfriend's sisters wedding tomorrow and we have come to help set up but we are staying in a hotel for the next 2 nights. However I stood in the room was it was bad. Everyone is happy but I am not. I was forced to come to the wedding but I really don't wanna go. It will be full of people and I really don't care. I haven't even got anything to wear for it so we are going to have to rush about tomorrow to try and find something to wear. I hate being like this. What should I do?
What should I do now?
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