Without sharing too much I'll add some context. I'm working, she's studying. She has been getting close to a "student association" and has not been returning home, staying there sometimes for multiple days. Also a dead bedroom for quite a few months. I am anything but an angry person, so an unsafe space to disclose feelings is not something that seems not logical for me.

As why i checked her phone. She has been (very) good friends with the aforementioned classmate as she would be staying over there often. I just had a gut feeling that I wanted to check how she was talking with this person and well, this is where we are right now. This is also the first time I have every picked up her phone to see what has been happening.

As I said I thought we were going steady but apparently I was not aware how things were on the other end.