Love? Honesty? What? I dont know anymore...?

more details.. uh...Before my boyfriend and I became "US" , He used to like this girl..very much. But that was like a while. We've been together for a year and almost 2 months. The thing is ever since we came back from summer * Just 1 month in the states* and when i get back home it's like he doesn't care much about me anymore...And i act the same way cause it just feels weird. Anyway its the 3rd week of school and my bestest friend told me that she and one of my other friends over heard my boyfriend and the girl the he used to like talk. and the girl, who btw used him, asked him if he still loves her. And they didnt get the other parts. My heart's breaking and i just don't know what to do. If theres any advise at all. Please. <3 Thank you guys....