How am i supposed to deal with my great love?

I was in love with a guy and i loved him so much. He broke up our relationship and we were in relationship again. But last night i was unable to talk to him and he got mad at me now he tells me he loves someone else. I know who is that person i talked to him and he said he doesn't like and don't love and he always talks about bad things about him. I don't like him at all. But the person i love he thinks he loves him. I love him so much it seems nothing is important for me wihout him. How can i prove my love for him is true and i never tried to hurt him? Please let me know i can't stay away from him and he is my everything i can do anything for it.