My girlfriend emotionally cheated on me
P.S. English is not my native language and this is my first time posting on reddit, so I apologize in advance if there are any mistakes.
I’m (21F), and my girlfriend—let’s call her Denis (19F). We’ve been together for a year and a half, and we’ve been living together for the past year and a half. A few months ago, I found out about her emotional betrayal. It all started when I noticed changes in her behavior: she was constantly talking to someone, going into another room, saying she was talking to her best friend, but in reality, that wasn’t the case. Although on the one hand it seemed like everything was fine between us, this behavior still bothered me, and I had no choice but to take her phone while she was asleep to see who she was actually talking to. Generally, I find it unacceptable to look at my partner’s phone without their knowledge, but then I realized that if she was already hiding something, she wouldn’t tell me the truth even if I asked. On her phone, I saw that Denis was chatting with another girl, whom she had labeled as “kitty.” After finding this out, I decided to read their messages, and they were very explicit and had clear sexual undertones. From their conversation, it became clear to me that they had never actually met in real life, but were just planning to meet up. But regardless, it was a huge blow to me, because I was absolutely certain that Denis would never cheat on me, and she herself had said so many times. The next day, I decided that we needed to talk about it. I asked her who she was actually talking to and who this “kitty” was. At first, Denis started making excuses, saying it was just a friend, then that she was just tagged that way but there was nothing between them, and she asked me if I suspected her of cheating. But when she realized that making excuses was pointless, because I knew too much, she confessed that she had indeed been messaging another girl, that she felt I wasn’t giving her enough attention, and that she had started looking for it in someone else. She cried, apologized, said she didn’t know how it happened, and that she hadn’t thought about the consequences; she begged us not to break up, saying she loved me very much and didn’t know how to live without me. After a few such conversations, we agreed that for now we would live in separate rooms like roommates and gradually try to rebuild our relationship, starting with just talking. But things quickly returned to our usual dynamic as a couple. But now I realize I can no longer trust her as I did before; from time to time, thoughts cross my mind: “What if she cheats on me again, but is more careful this time, and I never find out?” Of course, she swore to me that it would never happen again, but now I just can’t bring myself to believe her. I don’t know what to do. Right now, everything seems fine when I ignore these anxious thoughts. But when I think about it, I realize that’s not really the case. I love her and I don’t want to break up with her, but I don’t know if I’ll ever be able to trust her again.
TL;DR Should I wait in hope that trust will return, or is it better to break up now?
Is it even possible to regain lost trust?
Should I tell my girlfriend how I feel?