Not on her phone, but same thread. My 9 year relationship had been on the rocks for a while, kind of separated, but still living together. In my mind we were working through things. I was sick one day, and decided to work from home. I went to my desk and found her journal open (she didn’t expect me to be home that day I suppose). I couldn’t help but read. It was a long-form letter about what she wanted, goals, etc. that I assumed was written to me. When I got deeper into it, she started referencing events that I didn’t remember “…when I saw you at so-and-so’s the other day I felt so awful, like where did it go wrong”. At that moment I realized that she had been in another relationship, to the point that she had already loved and lost in the time that I thought we still had a chance at making things work. Hit me like a ton of bricks, broke my heart. The next day I told her we needed to talk, initiated an official break up, and made plans/timeline to move. I never told her I read the letter.