Please help me Friendship Problem.....?

My ex best friend(ari) back stabbed me again and again and i forgave her. She has this major crush on a boy who is her best male friend (joesph) but i hate him. I have another best friend(christine) who she doesnt like.Soo she ignores me backstabs me and steals my friend from me. Christine wont talk to me or listen to me. Ari sends Joesph nd tells him to tell me she aint my friend both of them aint so i told him i aint either nd Christine told noo im ur friend but i said i aint none of u guys friends and if u have something to say say it to my face, so everytime i with a friend Ari comes and whispers to them saying that i talk bout them behind there back but i dont