There can be several reasons. They can be jealous of something you have but they don't. They never talked to you but judge you from things they heard about you. You wear something that might not fit in their opinion. Maybe you don't look like they would like you to look. In my opinion, if everyone likes you, you do something wrong. I mean, we try to impress people with our clothes, our body, make-up, new stuff we buy. Never try to impress people that aren't worth it. Never change for a person just to fit in or to have friends. Real friends like you the way you are. It can be hard to be yourself and go your own way in a world full of judgemental people. But if you go your own way and haters don't bother you, then my dear, you do everything right!