Let me know what you think???

I went through my boyfriends phone and I saw texts messages with his friend saying this literally minutes before I picked him up… I only looked because he was being suspicious I’ve never done this before but now that I’ve seen this idk how to feel at all except hurt? Idk if I’m overthinking or something but I just don’t feel like that’s something you would say to someone behind your gfs back… let me know what you think?