My best friend is always judging me

My best friend is always judging me and if I wear something that shows even a little bit of chest, she calls me a tramp. It really hurts my feelings. At school, we have a newsletter. I'm editor and I'm also the advice columnist and she sent a fake letter to me saying:

that was word-for-word of the letter. I want to be her friend, but I don't want her to judge me. What should I do?