Huge Problem

I have a huge problem, even though I have never caught my boyfriend cheating on me and I've never found anything that would lead me to believe that he is or he will but one time when I went snooping and saw him talking to girls I dating websites. I understand that I can't accuse unless I have proof, but the way my mind is set up is like , well what if he is and I just don't know it. I have no urge to spy on him or go snooping, and I understand that if he is doing anything then it will naturally come to me but that's just nerve wrecking. I don't have the urge to go through his phone which I shouldn't.  Maybe I'm just crazy. Am I the only one that feels this way.