<human>: Provide a brief overview of the text.

Hello I am currently back together with a girlfriend of mine for 2 years. We had a large falling out 6-7 months ago and I ended up asking to break up because she had many malignant behaviors ie. berating, love withdrawal, assassination of character, fixation on marraige etc. I went no contact for that time because I did not believe she could change but started speaking again when I ran into her at a store. Over the past months together she has not shown any of those previous qualities and has been a joy to be with. Recently I was along at home playing on her mac and responding to a text to her while she was at work and saw that she had a conversation with a man she met on tinder. It was kind of sexual and really made my gut turn. My condition on getting back together was knowing what she was up to when we had separated and she knew that I would not take her back if she had slept with someone else. She had told me she went on dates but nothing more than that and everyone she met was through acquaintances. Well turned out she lied. She still denies that they had any physical relation and she only saw him once in public and didnt like him. I just see her in a totally different light now. It maybe my own fault for putting her on a pedestal. I can't really get over it without knowing the full detail and she won't discuss it with me, saying it's not my business. Its become a point of contention and I don't know if i can get over it without knowing the full truth. I realize its over and we were separated when she did this, but I can't seem to get my mind off of it. I keep wondering what else she had done and what else she could have lied to me about. I use to see her as marriage material but right now I honestly don't think I could see myself spending the rest of my life with her without getting over this feeling.
<bot>: Found out girlfriend lied about sexting on tinder w/ others only 3 weeks after we separated from a 2 year relationship