I remember being your age. This might be difficult to hear, but she is not interested. It would be fruitless to pursue her. Crushes come and go. Not everyone you are romantically interesting in will return that interest. But eventually someone will come along that will have a mutual interest in you.
While you are young, do research on this organization, it's history, belief system and so forth. Think about going to college and making friends with people of all religions and backgrounds, not just JWs.