DMP, stop now the snooping and the recording - you know already what you need to now - anything more is just masochism - Work on yourself because this is the only thing that really matters . If she is going to come back you have do be strong and confident, is not going to be easy to rebuild trust and you have to be in good mental shape to face the challenges ahead, with your W or with a new gal. Facilitate your W dating does not serve any purpose, don't be spineless like.... "I let you do it because I love you".... I am sure you don't like yourself like that. I am saying that because I kind of did that too and wasn't good nor for me or the relation. She is going to do whatever she wants, with or without your blessing, the difference is the way you look, and your integrity, so please defend your beliefs..... and you don't believe it is right to have affairs, so defend that.
I went to all the stages you described, and I know well how you feel, but I recently had my aha moment. Since last week I had an automatic answer machine calling my cell phone when I knew my W was close to hear, I am happy and party like at the cell, I show I have friends, I am living a great life.... I could win an oscar for acting... some girls really really want to go out with me (I wish it was true:) Strangely enough I started to feel better, and started to blend imaginary with reality... I am actually getting a life. I can tell W is bothered - yesterday night she called me late at night - she wanted to talk - "are you alone? she asked" I wasn't I was having a blast with some friends (for real), ok talk to you later..... No illusion here, I am sure she was just having a moment of loneliness, but boy did I feel good. You cannot change your W..... simply asking her to change.... but she may realize she screwed up big time with HER life and she'd better change.