Hi.
If you really believe in what you are doing, you should follow your beliefs.
Does your mom really hate you? Does she understand what you believe in or is she jumping to conclusions? It sounds like the topic may be a really charged one between you and your parents. Maybe you need to give them a better idea of what you believe in. Sit down and talk, maybe find some books that explain what Wicca is and give them to your parents, or sit down one night and talk about the book with them.
It seems like people at school could be jumping to conclusions. You could ignore them all and remind yourself that they are probably feeding off a distorted image of what you believe in.
But if you have doubts, and feel like you want to fit in better then you may just want to decide where and how you can do that. I don't know you, but I imagine that your religion is only one part of your life and of yourself. If you have other interests like basketball, or drama, maybe you can pursue them, and be more involved with people who may just be confused about what you are doing as a witch. Getting to know people in other situations might allow them to see you in a different light.