Confused.

Kelly • 757 | 21
Ive been dating the same guy on and off for about 3 and a half years now. He's the only one ive dated though, and he is actually my first. I think i love him, but he is my first real relationship. All my other relationships were adolescent, and nothing like this. We basically lived together until he joined the navy and im still waiting for him to graduate from bootcamp. And we saw each other everyday. We fought a lot, and i feel like its because i dont trust him due to past events. He and i are trying to work things out but we arent offical anymore (since this feb). He tells me he loves me but i dont know if i trust him still.
But its crazy, because when i think about him i cant help but smile real big. I get excited when i talk to him, and i think of him everyday. Im so confused though because i have no idea what love feels like, and i dont know what to expect. People always say "when you love, you just know." But i love when he and i together. He gives me the feeling of comfort. Idk what to think, or what to do. 
​Anyone have any advice for me? Please help.