Guy's Behavior

Is he cheating? Hickey or bruise?

First, a little bit about the past of our relationship: There was a girl in the beginning of our relationship that was very young, that my boyfriend was trying to "help", (she was a mess, her boyfriend was in prison, etc.) She was very much the other "woman". He would say things like, "So and so is going to be pissed I'm not at work today." Now, he's AA and feels obligated to help out people who play the role of victims. So this girl started calling him all the time. He didn't hide this from me. I made a HUGE deal about it. He saw nothing wrong with his behavior, saying she was a friend and that she reminded him of his sister, note: there was some weird sexual stuff in there, like him reading Cosmo to her for "fun" at work. I chalked this all up to him being stupid. She is out of the picture now. A year or so later, we moved in together. We got into an emotional rut and he disappeared for three weeks saying he needed a break. Suspicion on my behalf that there was someone else, but I have gotten past that (until now), and things have been amazing since October. The other night we were in the dark in bed together and he suddenly mentions that he has a bruise on his stomach. He says that to avoid a crowd of people at the gas station he walked through a narrow area and a sign jabbed him in the side. I immediately felt he was lying. I asked to look at it and he complied. I said, "Looks like a hickey." It was red and splotchy. But - if it was a hickey why would he have told me anyway? Then the next week he received a text on his phone from an unsaved number saying something to the effect that "she" was lucky to have him, an angel, in "our" lives. This could have been a family text, as he's been going through some family stuff. I didn't ask him about it. He is otherwise amazing, and doesn't display cliche signs of a cheater. It's mostly trying to differentiate paranoia and that "feeling" that's tripping me up.
Is he cheating? Hickey or bruise?
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