hi Darren, I just have a minute here to post, but I just wanted to encourage you. It is so wonderful that you are concerned for your family, that devotion will help you find the strength to do what you will need to do.
I'd have to agree w/trying to survive that your A is most likely not as hidden as you think, in my case I was pretty sure even when my H kept denying it, my kids knew, the neighbors knew, I pretty sure coworkers know (ow, H and I all work together) If you are feeling so torn and guilty, your wife is picking up "vibes" in your eyes an your voice. I would be very surprised is she doesnt know "something" is amiss. How you handle things I believe needs to be based on your R w/your wife. You probably know her better than anyone. I can tell you she is going to need a lot of patience and understanding on your part in order to heal. She will need your help.
I have to agree w/Survive about the ow...the ow my H has been involved with had her husband have an affair, and he ended up marrying the affair partner, so she had to know full well the pain involved, I believe she probably purposely did some of it out of anger....I ran into her in the breakroom here at work once before I knew about the A, looked in her eyes, and have never in my life seen such hate and anger - for me! I spoke to her and cold hate dripped from her voice. I literally spent hours and days trying to figure out what I had ever done to her. so I truely believe that if ow has had multiple A's, there's probably a "get even" quality to it. ow also have personality characteristics that are pretty universal. as one of the books I've read puts it "any woman who makes herself available to a married man has issues and problems of her own...these generally include a distant relationship with her parents, especially her father; prior sexual abuse; problems with low self esteem...and it listed several others, which I don't recall at the moment (this is from "Men in Midlife Crisis" by Jim Conway. So, my point is that although you have certainly errored, you are not 100% responsible, and your ow is not the innocent victim she needs you to see her as. Let me guess...she doesnt readily accept your efforts to end the A, does she? She always has some little reason, some innocent appearing request to draw you back into her web of neediness that ends up with physical contact, right? and then the physical contact causes the release of brain chemicals that starts the whole process all over again. I've seen it happen with my H more times than I can count. and I can guarantee that the ow is not going to be the one to call it quits, you will have to do it.
I really suggest getting ahold of "Not Just Friends" and giving it a quick read before you do much else. It has specific suggestions for dealing with the intrusiveness of the affair partner after it has ended. Acutally, regardless of your age, you would benefit from reading the "stuff" about affairs in "Men in Midlife Crisis" as well....
Do you have any type of religous affiliation that you might be able to get some forgiveness from ????this may be a great help to you. Do you have any men you respect who have dealt successfully with a similar situation you could discuss your this with (much easier said than done, I know, but it could really help if you have the right person to talk with) or have you considered a counselor?