I so sorry man. This is new to you so everything will be up in the air. Believe absolutly nothing she says and assume the worse. Please trust me on this. You will be getting the trickle thruth.
Funny, I was with my wife 13 years ans married 7 before she decided to be a whore, or worse yet, she had always been one and just found out. Anyway when I caught her 9 months ago, she advised that it was a 3 month affair and they had protected sex 3 times. We started R. 6 months into R, after cracking her locked iphone code, I learned that the A was a year long, they had tons and tons of unprotected sex, they had a few pregnancy scares, and she was still seeing him while were were R. Be carefull. Expect ANYTHING.
It may be too soon for you to implement the 180D, but if your too weak, at least review the rules. I recommend that you 180 her ass now.
Im so sorry. Im new to this too, my advice may no be perfect.
Based on my research, case studies, and experience, she was about 5 steps ahead of what she says she did. So if she says, "hes just a friend", its more. If she says the only kissed once, that means they made out a bunch. If she says they almost fucked or "just did it once", that means they fucked 10 times, and so on.
Please, do not beg and plead, she will see u as week and will walk all over you. . I did this and she mocked me.
Do not stay in limbo. I did this for 7 months . It was pure hell. Pure hell. You dont have to make any crazy decisions like divorce and selling the house, but at least start the 180D. It will either push her away to the OP, or she will hopefully come out of the fog and want to R.
This site is great. Lots of help here.
Good luck my friend.