My STBX and I recently separated. Due to my loneliness, I reached out to a woman from my past that the STBX had issues with. I had feelings with said woman but never acted on them because I was married. Now that her and I are “available” (she is going through a divorce too), our chat became x-rated quickly. Meanwhile, I left my old phone at my STBX place and didn’t reset it before I left. She turns on my old phone and notices the text messages because we both have Apple and I didn’t reset the phone messages still went to that phone via WiFi. She sees them and gets angry and upset with me. I explained that we are over like what she said. In her eyes it comes down to she hates the other woman.

I need some advice about this. Is this nothing because we are separated or could she use this against me? She is also seeing someone else too prior to me moving out and us separating.