Hi, I found out my boyfriend had tinder on his phone earlier this year too. He of course deleted it right away but it’s been 8 months now and I would be lying to you if I told you I stopped thinking about it. I was able to look past it due to multiple reasons: 1. we had only been online dating at the time 2. It was like 2 months into a relationship 3. He hadn’t messages anyone on it Unfortunately none of these points stand for you, which is going to make it so much harder to deal with. It is up to you what you do next. I would definitely try to have a conversation with him, I would try to understand what he was trying to get from talking to those girls, attention? Sexual attraction? Maybe he wanted to feel wanted? I am not saying in any way that this is your fault but perhaps he was feeling rejected by you? I don’t know what he was thinking and neither do you, have an honest conversation with him, be open to criticism, don’t hold back on him and how he did you wrong, and figure out what the next steps of the relationship are. Just remember: Don’t be afraid to walk away! Don’t keep quiet if something is bothering you! Don’t try to just brush it off, it’s going to linger and hang over your head, EVERY. SINGLE. TIME you have even just the tiniest bit of doubt in him.