why cant i get over him?

me and this guy used to be friends and we liked each other, in a more than friends kind of way(i mean, i liked him and i think he liked me too) but there were two problems; the first one was he couldnt admit it and the second, he acted like he still had feelings for his ex. I never cared about his feelings for his ex at first i just wanted him to admit his feelings , coz i couldnt, i'm the girl and he's theguy and he's supposed to be the one to admit it but it never happened, he never said it but he often got jealous when i was with other guys. This went on for sometime but we still remained friends, i mean, at least we kept on talking to each other. It was then when the thing with his ex started bothering me, i really acted like a ***** and said real mean stuff to him, i felt guilty and wanted to apologize but we had already stopped talking and i was sort of sit was evident that he wanted to move on, it was like he never wanted to talk to me and when he did, he talked in a rude way. I was not over him, i still aren't and i've been desperately trying , now that he and his ex are always hanging out and he speaks rudly to me or doesnt speak at all, i feel left out. I really want to get over him but how can i, i really dont want to get jealous when i see him with his ex but how can i do it?