Why does my ballet teacher hate me?

My ballet teacher has always ignored me in class but it has gotten worse in the last year. She now openly pulls faces at me if she does not like the way I am doing an exercise, but does not help me correct it. She talks to the other mums, giving advice for their daughters during class , and helps the other students all the time - stopping the music when they have done something wrong, helping them and holding their leg/arm whatever to show them how it must be done. She never looks at me. I am probably self taught -and have done well in the lower levels. Now that I am in the vocational levels I am finding it really depressing as I can not manage - I need a teacher to help me and she ignores me. It is as if I am not in the class. I cry before class, during class ( she seems not to see) and after class and am beginning to hate being in her class. We live in a small town so no other teacher. I have done well in exams and competitions as my mum tries to help me at home and I work hard, very hard as ballet is my passion, but she has slowly killed it and I feel as if I have nothing left - despite apparently having natural talent for dance. Some one said she may be jealous as she never managed to do well and had wrong body type for classical ballet whereas I have the right ‘type’. It is as if she wants to destroy me. She never has a kind word to say to me and I go to class , smiling, and I work so hard - my mum says she can not understand it - she must be insane to be able to treat some one so badly and so openly - she obviously does not want to teach me