[inlove?&confused]

For the past two months I have had a hard time trusting my boyfriend. We have been together for over a year now and have become very involved with eachother. He is older than I am and able to go out to bars while I am not. I am away at school and am not able to see him very often. I have noticed lately that I become aggrivated and a little mad when he goes out and parties with out me. He has never given me a reason to not trust him but for some reason I can not get the idea of him cheating on me out of my head. The only reason I have to not trust him is that a unreliable source told me that he cheated on a previous girlfriend. I have asked him about this and of course he denied it...but who wouldnt.

We have a very open relationship and try to talk to eachother about everything that bothers us. He has noticed my bad mood after he goes out with out me. I do not want to be a controlling girlfriend and I Want him to go out and have fun without me but I cannot seem to control these very strong emotions. He confronted me about my bad mood and I told him that I was afraid that my moods may pull us apart and that I did not want him to start lying to me about what he is doing or where he is going in order to avoid my moodiness or an argument. He then said, "Honestly, if this keeps up, it would be easy for me to just not tell you." Or in other words lie to me about what he is doing. I could not believe he said that to me. I do not know what to think of it. I honestly love this guy and do not want to lose him, i just dont know how to trust him and how to deal with my emotions. Please help me!!