My friends always seem to point out my flaws. I admit that I have insecurities, but they point things out that I don't even mention. (And no, I never have mentioned anything related to them—they're all beautiful on the outside and I could never say anything like that to them.)
They'll say I have a big nose or small teeth. I don't know why they do this. Sometimes it seems like they're in a bad mood when they do this so maybe they are just lashing out at me. But it hurts and when I question them about it, they don't say anything or pretend it never happened. They have other friends, but I think they only do this to me. Is there something I'm doing wrong?
You haven't told me your age but persistent teasing such as this is very childish and immature—and is totally unacceptable behavior at any age.
Since your friends don't do this to other people, it may be that you are doing something inadvertently that is provoking their criticisms.
1) You point out that you have some insecurities that you do mention to your friends. Perhaps they think that this gives them license to heap on some more. If you are sensitive to other people criticizing you, try to ease up on being the first one to point out your own flaws.