I was using my mates tablet (not intentionally snooping. I just needed to look something up). During the middle of my use, a message comes up from a girl asking to meet. Curious (ok, now I'm snooping) I clicked on it. I read through the thread and it included some nude, sexy pictures of a girl. I looked up her name, and it turns out she lives in the next town over from us. Earlier that day, he went out to the store to pick something up and then told me randomly afterwards he needed to go into work to do something (which rarely ever happens). I couldn't tell what he was replying back to her, but judging from her comments he must have been flirting. He is being discrete about it, tying it to a separate username/phone number that I would not be able to otherwise see on his phone or computer. Is this something to bring up with him? There was no hard evidence he has been cheating, but the conversation sort of leads to it. If not physically, at least emotionally. There was a time way back when we first started dating 4 years ago I came across a similar situation, but never said anything to it. It's been bugging me ever since what he is/isn't doing behind my back, and now this shows up.