My GF and I have been together for a year and a half. In january, i looked on her phone and found that she had messaged someone on christmas eve. Now the message was rather innocent,a little flirty perhaps, but the fact that she messaged him at all really hurt. Because, as I scrolled up the message thread, i found naked pictures and videos they had sent to each other. Granted this was before we were together, but now you see why it hurt so much that she would even message him to begin with. It hurt to see her doing with this another man, and it hurt because i did not know that she was that kind of woman, to make it worse, this was a married man she was doing this with. It gets worse.....A week ago, i looked on her phone again, this time to do a good search...well, before i continue, let me clarify that all that i found happened between 2014 and 2016, leading up to one month before we were together. I found out she was part of an amateur p0rn group that posted pictures of themselves. I found out that she had sent pics and received pics accompanied by dirty message talk with over 20 different men while playing with themselves, her too... a few of them were married, as in one message when she was asking where his wife was, but did not stop the hot pics and banter, she even had physical relations with some of these men (none that were married that i know of). I realize it was my own fault for looking in the first place, but the damage is done. Regardless, I told her it wasn't fair to have not told me this at the very beginning so i could decide if i wanted to give her a chance by accepting it or not. After all, i had revealed something to her that could have been a deal-breaker that was very personal and embarrassing, but she deserved to know. As did I. I told her i was leaving and she begged me to stay. I know she loves me, of that i have no doubt. She claims that she just wants to put it all behind her, she is ashamed, and that she is not that person anymore (but why message this guy on christmas eve?). She has always been so kind and loving and sweet, and that's what makes it so difficult, to see her give herself away like an internet wh0re just breaks my heart. The image of my sweetheart, shattered. Just to know that she would be capable of such indignant behavior is hard enough, but to have actually seen the images and read her words to other men, and theirs to her, i really have no words to express the emotional horror that dwells inside my head. I try not to think about what i have seen and read,with so many other men,try to realize it was in her past,and have since told her i would stay. I have been trying to deal with the extreme discomfort of having seen what i had seen. I have good days and bad days, but i always pull through. I think about leaving as a real possibility as the only means of truly dealing with it and keeping my sanity. Any advice? How the heck does one get over such a traumatic shock to the heart?