self conscience

My family constantly puts me down about my body. They don't mean harm and I laugh it off but I hate when they point out things about me that other people in my family don't have. Like my butt is big for a girl my size. And they assume I'm having sex. Mind you I'm only 16, they also say things like I dress like a prostitue. But all my clothes have to be fitted because my waist is very tiny. A size 0 and I have to go up to a size 3 to get my pants all the way up. I don't feel as if I dress like a prostitute because I'm fully covered. I I need some advice on how to tell them pointing out my flaws hurt my feelings .