Well Greg, sorry that you have to end up here. Believe me, you will get a lot of advice on this site and I would suggest that you read through as many of the posts that you can to find something that fits your sitch.
I guess I can give you some of my insight simply because I have been in your shoes. I once was the cheater and not the cheated. While you really don't go into any great detail, I recognize some of the feelings and thoughts that you are having. Truthly, I have no doubt that my W is also experiencing these right now.
Back to you....the reaction that you got from your W is not atypical. My W, after her intial reaction, was the same way as well. Probably the best it had been in years. At first I was tentative, wasn't sure whether it was what I wanted....part of it too was I was still pining for the OW. It took some time, but the more I moved out of my fog and took a good hard look at my W and our M, the more I realized that it was what I wanted as well. I had overlooked so much of the good to justify my actions, that I was only able to see the bad.
Now, for the kicker. The problem....I didn't recognize that the affair was only a symptom of some larger problems we had in our R....lack of communication, emotional attachment, as to say the least, the emotional damage that it caused to my W. This all added up to some pretty hefty stuff for her and now I find myself in the same situation that she was in two years ago.
The point is, please give your W and your M a chance. Look at it objectively and try to recognize the good. Also realize that you and her both should try to establish what was wrong in your M that led to you having an affair. There are a lot of good books and articles out there thay may be of help to you....and others may have a much better library to offer you. For my part, I would suggest starting off by reading Divorce Rememedy and Divorce Busting to gain some perspective on how you may be feeling and also what your spouse may be feeling.
Good luck.
"Achieve success, but without vanity; Achieve success, but without aggression; Achieve success, but without gain; Achieve success, but without force." Lao Tzu