Guys, please stay with me from beginning to the end, your help is needed and appreciated
So, I already wrote some months ago here that I found out my GF of whom I thought is the best, most honest and other AFC crap, would never cheat or lie to me. I concluded that if she lied, she also cheated so I broke up with her. She explained the lying as she did not want to hurt me and make me suspicious (she met her ex behind my back and lied about it) and destroy a beautiful relationship with me over something I would not understand. Well, bit by bit, I put the puzzle together and realized that the heart breaking story of her meeting her ex who was devastated by the break up actually also included her sleeping with him during that time. To make it even worse first she lied that he only slept at her couch crying because he was devastated and she felt sorry, then they only made out, eventually after few months of our break up I cornered her to confess she had sex with him and met him also another time when we were deep into our relationship and were as exclusive as we could be.
So, even though I was crazily in love with her and suffered quite a lot (she is quite good looking and "talented"), as soon as I learned of her lying I left her without any drama and acting as cool as possible. She continued contacting me crying and begging for some months. However, the fact that only when she was completely cornered she confessed me the whole truth of sleeping with her ex, and even then not saying all the things that actually happened made me quite angry. Since we broke up when I checked her phone and realized she met her ex during the period she said she could not meet me because she was busy (please spare me the bs of not having to check her stuff; suspicion+check=me discovering she is a big bitch) I learned some very interesting stuff. She lied even to her ex boyfriend blaming him for the break up. The reasons being quite Oscar winning, - she confessed to him she liked a guy (me) but did not have anything physical with him just platonic meetings (awful bullshit, we were sexing for a month then, few times a day). As I learned along the way, the guy was really a poor nerd without to much experience and worshiped her as a goddess "half-virgin" girl she presented herself to be. Unfortunately this continued up to today (she feeds him with this stuff) and the poor bastard lives in the illusion that if he was less "insecure" and jealous he could still have her.
So my, dilemma is should I send an email to this guy, just telling him the simple truth and letting him do what ever he wants with this information or should I just let her continue destroying him? The problem is that she is really good at selling herself as an innocent Muslim girl who just seeks true love. I am hoping that by contacting the guy (against whom I really do not have anything) I might as well finally find out the whole truth about her and finally find my peace.
Thanks in advance for your input guys, I really appreciate.