Well, therapy isn't always necessary -- though, I'm not qualified to say if you really need it or not.
There are other alternatives in some situations--
If you could find someone that you felt comfortable in talking to and was a good "role-model" type person. If not one of your parents-- as I understand sometimes it's just too hard to tell your parents some things--- then maybe one of your friend's mothers..... some moms are very good listeners. (not meaning dads aren't good listeners, just that you are a female so it might be best at this time to talk with a woman)
Oops!--I had to "edit" the post to add this-- I forgot to put it in the original post---
Also-- perhaps there is a female teacher that is kind and understanding that you could meet with before or after school and talk with her. ----- just some ideas....
I wish you luck with this.
mandy