To add to Starsky's post, I, too, was successful with exposure, but didn't do it for almost two and a half years because it wasn't advised. For me, it was the shakeup that my sitch needed to finally get through.
In my case, I did not go to everyone with the affair- I only exposed to the OM's wife. They have kids, I have kids, and I didn't want my family hating my W for her mistake. I went to the OM's wife because he wouldn't let my wife end the EA, he kept coming at her, challenging why she didn't leave me as she said she didn't love me anymore. I needed his W to help with ending it (she had no idea why her marriage was falling apart- he lied to her about having another woman in his life).
If I had to do it over again (not that I ever want that pain again!) I would have told the OM's wife right from the off.
What specific changes are you working on in yourself? What do you think the OM provides for your wife that you weren't providing in the M? What do you think that you can provide her that he wouldn't be able to (certainly being the father of her children falls in her)?