Can't take it any longer!

The mocks are almost over and they are going fine, it's just that I really need to post something!

My art teacher has pushed me to the edge! She keeps on saying that my work isn't good enough and doesn't listen to what I'm saying. And the worst thing is that she keeps on accuses me of copping other peoples work and looking down on them like dirt.
All she does is criticise your work and doesn't give you any help or encouragement!
I really want to do art in collage and I want to do well in it and I love art but it has come to the point that I just can't take it any longer with her!!
I don't know what to do?!?