Cheating is near impossible to get over. It can be done. It can be forgiven, in time, lots of time, but it won't be forgotten. Because if it ever happens again, then that first time will be dredged up. It will remind you that you already forgave.
I found out about all of them at once for me. I kind of always knew about L. She was the threesome we had where she stalked my husband and he slept with her later on. She was constantly calling and texting him. When I would pick up the phone she got very hostile. He knew I didn't like her yet he never ignored her or told her to go away. I finally did that. L was his brother's roommate. It was just too easy to go "visit his brother". But I would always ask and he would always deny. I had no proof. Nothing to go on except my gut feeling. So I kept letting it go.
When he finally admitted it burned through and through. It burned deeper than J. Even though I had become friends with J and had broken promises and words from her as well. The fact that he slept with someone as evil as L, and yes she is evil and I hate girls like that especially when they get what they want. She is a slutty drug addict that if I ever face again I might knock her head off and I know I could take her.
Mohegan - You have worded why you are trying to forgive and work things out wonderfully. Those are all the things I have felt as I try to move past the cheating. It isn't so much him sleeping with someone else or the cheating. That part does hurt, don't get me wrong. But the lying takes away so much from the marriage. The lying strips away all belief, trust and communication and is so hard to get back.
I love DH so incredibly much. But he knows I do not trust him anymore. There have been too many lies. Even after I found out about J. He has attempted to lie again. But I watch him so closely now that he is caught very quickly and last time I almost walked out. I told him he might as well keep his date with J because I wouldn't be home. It had nothing to do with J this time. Why punish her? She has not lied to me since. At least that I am aware of. And I trust that she hasn't.
DH I watch so much closer because for some reason he finds it harder to be honest with me. When I almost walked out he came after me. He wouldn't leave my side all night. I have to admit I sat around and did the most boring stuff to see if I could bore him enough with my night. Wanted to see how serious he was. And he never budged. Just smiled and spoiled me rotten. He has been open more since then. I have questioned him even more. That is just how it goes. I love him, plain and simple. And as long as we are committed then we can work through this.
I hope you feel the same in your marriage. It is so hard and takes so much work. Many people will say it can't work. Cheating into polyamory. But it takes change for all parties involved. It takes communication not just with the husband and wife but with the wife and gf (husband and bf, or whatever the combination). I hope in time you will be able to talk to her. You might be surprised when you hear her answers to the questions you have for her.
You want to hate her and call her a whore and a husband stealing bitch. That isn't always the case. J is not that case. I wanted so much to hate her in the beginning. But DH wouldn't let me. He did everything in his power so I wouldn't. And I am glad. And now I don't. She is a very dear friend.
I still have a hard time with them being together. He is my husbband after all. But if this has to then I am glad it is with someone I care about as well.