He doesn't trust me

My bf of 2 years doesn't trust me. He says he does but the only reason why i think he doesn't is because everytime he calls (we have a long distance relationship) he asks what I'm doing and I tell him i'm watching tv or something and he says uh huh sure who are you with? I say no one just my roommates (who are guys but one of them is my brother & the other two act like a bro) He says why are you breathing so hard then? I said i'm not i'm just breathing. First time he did this I thought he was just joking but everyday since then he keeps asking these kind of questions. I have told him your driving me crazy and i'm not doing anything and I would never cheat on you or anyone for that matter.
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Talk Dirty