Well, I had an affair too so I understand how you feel. What I see from the few posts you've written, and something that was very evident in my situation, is that you need to look at why you felt the need to get into the affair in the first place. You've had two failed engagements and an affair. What did you feel you were missing from these women? What did you expect from them that they weren't providing? Why were you here two years ago only to give up on that relationship and enter a new one? What made you feel getting engaged to your recent fiance was the right thing to do?
A lot of questions and they may sound harsh. Good news is that the vets recognise you. Bad news is that it's time to grab a shovel and start digging into your soul. Good luck!
Me: 31, W: 29 T: 4 M: 2 Kids: 3 (SS: 7, SD: 4, D: 3) Separated, still living together: Nov 2013 Separate bedrooms: Feb 2014 W working away; kids with me: Nov 2014