Should I break Up with him or work it out?

Okay so I'm dating this guy who lives 4 hours away. He's everything I'm looking for in life and we share a lot of similar things...he wants to call me and drive up and see me but he hasnt yet. We have had a thing for over a year now..the problem is I dont trust him 100% anymore. Last week he sent me a text asking if I trusted him I told him I had no reason not to and then he said so you would have no reason to be mad if I went to lunch with an ex..I said go ahead cause i was kinda hurt. then he said they were just friends and ever since we have been fighting. Last night he went to a party and told me he had to share a bed with 2 girls his brothers girlfriends sister and her friend. I told him to have fun.. and then we didnt talk much that night I then texted him today and since about a week now he has seemed distant and I get a bunch of one word texts. But he claims to be happy with me and we both say we love each other. I know it's confusing but I just want to know if I should break up with him or how we could work it out. BTW he's 19 and Im 15...thank you :)