How heavy is too heavy for a girl?

A lot of people talk so much about weight and recently something humiliating happened to me. We were dancing in school and we ended up having to do lifts but I had to walk off the dance floor because no one could lift me. I’ve been anorexic so this was really bad for me but I don’t even think I am that heavy so how heavy would you say is “too heavy”?
How heavy is too heavy for a girl?
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