Hi, I'd like to describe a situation that's been bothering me and ask for some advice on whether I should even talk to my girlfriend about it, and if so, how to bring it up.
A little background: We've been in a relationship for 5 years. The first two years were amazing. Then, she went away for university, and we were in a long-distance relationship, which was still okay. We've been living together for a few months now, as I moved to her city while she's finishing her studies.
Anyway, during one of her student outings (2 years ago), she met a guy with whom she really hit it off. I think they ended up at a rave together until the early morning (I'm not sure if it was just the two of them or if they were in a group). She told me about this herself. After that, they texted pretty much constantly for several months, sending a lot of messages every day. I once glanced at a few of their messages and I didn't like their vibe; I felt she was very emotionally invested.
I confronted her about my feelings. She apologized and said she didn't realize I would see it that way and that he was "just a friend." In any case, they continued texting for a few more months until he ghosted her. They also met up a few times during that period. I was not a big texter so I get why she might have needed that.
Sometimes, this situation still bothers me, and I wonder if it was genuinely just a friendship and my own insecurities are taking over, or if there was actually something more to it. I started thinking about it again recently when my girlfriend got so drunk that she didn't really know what was going on (this has happened once before in the past).
She is really lovely and really cares about me, and always helped me through my dark times, but nevertheless, it keeps bothering me. I don’t want to accuse her of something without any proof, but I feel like I need some kind of resolution to move past this. How can I bring this up constructively?
tl;dr: Two years ago, my girlfriend of 5 years had an intense emotional friendship with another guy that felt like it crossed boundaries. I confronted her back then, but her explanation of "just friends" didn't fully resolve my feelings. She is a wonderful, caring partner, but this old issue still makes me insecure. How do I bring this up again to find peace without accusing her or damaging our relationship?