Please help me get through this heartache?

My fiance that just proposed broke up with me. We've been together for 2 years and 13 days. We were going to get married next year when I turn 18. He broke up with me because I talked to my ex boyfriend which I didn't know that he would get this mad about it. He told me I could talk to him before, but he changed his mind and I didnt know it. He went to my myspace and seen that I talked to him but for some reason he couldn't see what we talked about. I told him we just talked like friends do, but he still called me a cheater for talking to him. He told me to delete him from my myspace, but I refused because I told him that means he doesn't trust me, so he said then if you don't its over. Good reason for him to break up with me or not?Then, he calls me back and says he didn't mean that he doesn't trust me ,but still calls me a cheater. He said he loves me, but obviously he can't trust me. I just need opinions on this and plz help me in any way..thanks..