See a doctor. As soon as possible. Try to get some councilling, talk to someone. I'm sure that your school should have someone in that line. On the line of furry, I hate to say this, but if your mum is against furries, she should be much more mature about her tolerances. Don't hide your furry stuff or whatever, if she starts asking - and she openly admits that she dislikes them - ask why, don't be afraid to voice your own opinion on the subject or question anothers, I mean, if they're questioning yours, isn't it only fair you get to ask them why they dislike?
That's really all I can say, try to detach yourself, try something new, something along those lines, but whatever you do, make sure you try to talk to a doctor about what's going on - any professional advice center will do, just try.