1. He's open about new friendships. So he made some friends at his bro's party or at work, which is normal since that's the polite and friendly thing to do. He casually tells you something funny or amazing that happened to them as he talks about his day. It's all good, really. For one, he has nothing to hide. More importantly, you're the person he talks to about everything, and you're the person he wants to share things with.
2. He's relaxed as he tells stories about other girls. Unless, of course, it's about his colleague you know he hates with all his gut and he's ranting to you about how she messed up again. Otherwise, if he suddenly doesn't become evasive halfway through his story or doesn't sound nervous or uncomfortable when he's answering your questions, he's not cheating on you.
Also make sure to pay attention to what exactly he's saying about other people. If he's ranting about them for affecting his work or for just being annoying on Facebook, that's acceptable. If he's telling a story that's related to something you were just telling him, he's just making and adding to the conversation. Make sure you know why he's bringing them up. Also, check if he talks about any of them all the time. If he does, he might be crushing on or beginning to like someone else.
3. He's still very present in your relationship. Usually when a person becomes distant, it's because something's bothering him or his feelings may have changed. If none of that happens you have nothing to worry about. Especially if your connection is still as strong as ever, and he initiates some dates.
4. He still spends most of his time with you. Well, technically he spends most of his time working. But if he spends most of his time outside of work with you and is clearly having fun, how can he see someone else? It's physically impossible and emotionally unthinkable on his part.
5. He feels loved and utterly satisfied. Some guys cheat because they feel that something's missing in the relationship (but it's a pretty decent relationship so they're hesitant to end it). They might not feel loved so they go looking for it, or they might not feel desired so they look for someone who wants them or lusts over them. But if your guy thinks you are it and feels 100% satisfied and happy with you in spite of the dark days, he's faithful.
6. He's an honest person. Cheating has A LOT to do with dishonesty and questionable principles. If your guy is straight up an honest person and not a hypocrite (some guys who swear against cheating are cheaters themselves), he's not cheating on you. It's out of character.
7. He's very comfortable with himself and with you. Some guys cheat because they're insecure that their girlfriends seem to be more successful and have a lot of things going in their life. Those guys want to feel strong or "masculine," so they take on someone else for comfort to feel like they're supporting her. But if he's genuinely happy for your successes and he's not insecure or letting his insecurities get to him in a bad way, he's not cheating on you.
8. He's not overprotective of his phone. A lot of people find out they were being cheated on by going through their partner's phone. (Snooping isn't a good thing to do, but cheating is abominable!) Since he uses his phone to communicate with everyone, you can bet that if there's someone he shouldn't be flirting with, their convos are in his phone. He knows that too, so if he's iffy, panicky, or paranoid about leaving his phone with you, you have every right to suspect. (Assuming of course that you're not clumsy and his phone isn't brand new!)
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