I do appreciate all of the responses and suggestions. It's good to get a variety of viewpoints and opinions. This discussion has given me a lot to think about.
I want clarify a couple of things. I understand that the RA was wrong. Believe me, I've spent a lot of time coming to terms with that choice. Since I'm being honest here, it did help me in some ways. From that act, I knew the A wasn't about me and I don't suffer from some of the typical BH insecurities you see frequently posted. I knew I could still attract a beautiful woman, pick her up, sexually satisfy her, and have her wanting to see me again. I knew I wouldn't be forever alone if I split from my wife. I knew I had options. The downside was I became what I freaking hated - a cheater, just like dear old dad. I couldn't do the mental gymnastics to rationalize what I did or to continue the behavior. I broke vows and lost my integrity because I wanted to burn my wife and prove my manhood to myself. I felt guilty and regretted my actions immediately. I wasn't thinking clearly and made a poor choice in the midst of an emotional crisis. It also did not impact my WW the way I thought it would. For me, the bad outweighed the good. It still bothers me to this day. I also know I would never have cheated if my wife remained faithful.
I have to admit, I am unclear about the whole EA thing. We read 'Not Just Friends' and I see how I was on the slippery slope, really any opposite sex friendship could be, but I don't feel I crossed the boundary from friend to EA. There were no I love yous or 100s of text messages sent. No crotch pics were exchanged either. There was no swooning. My WW and the MC we were seeing at the time felt differently. I think my WW felt threatened because of her behavior and projected her issues onto me and my friendship. The opposite sex friends thing can be a tricky situation and I did change the nature of the friendship.
I do feel like I've wasted years of my life Dr Stupid. It's too late for woulda, coulda, shoulda. I don't know if her metamorphosis is because we have a comfortable lifestyle with our combined incomes, retirement should be comfortable and on schedule. She also has an intact reputation with her children and almost everyone else she knows. In other words, I'm a comfortable plan B and she really can't do better now. Divorce would certainly change some of these things. Or if she truly has grown up, realized her wrongdoings, loves me, and wants to make amends.
I totally understand you wondering if she's being genuine or not. She has a lot to lose. Do you think that you do? The fact that she posted on the other message board means something, although, the fact that she pointed that out to you may have meant that she posted it knowing that you'd be in the audience. Is she being manipulative? That makes me feel uneasy about her intent.
What makes me direct my comments more about you than about her is that you've spent so much time hiding your true self from her. If you were willing to spend that much time in limbo, what's another space of time spent finding out if she's being genuine? After all, how could she meet your needs if she didn't know what they were?
I believe that people change, and often for the better, not as much once they're set in their ways, but certainly from being young adults to mature adults. That's why relationships break so often in those earlier years. You weathered many years where you both matured and grew, hopefully for the better. You're different people from when you froze your emotions in time. Is she a better person? Well...
The "kissing incident" a few years ago certainly was a HUGE mistake on her part. I totally understand why that would be a worrisome situation in the best of relationships with no trust issues, but with your baggage, that can be a devastating incident. I can completely understand how you'd be wounded all over again, or at the very least, receive confirmation that she's just as disloyal as she always was.
I'm not saying that you should reconcile. I'm not saying that you should leave her. Only you will know the answer.
All I am saying is that you suffered for so long, for a noble reason- the well-being of your children, and it would be nice for you to take the time to find out if your wife is truly remorseful. You gave her no opportunity to show remorse all those years, because you swept everything under the rug. Once she found out that you didn't forgive, then she reacted.
I can't tell you how many times I've seen people hang on to a cheater, and wanted to scream at them, "Stop being a doormat! Leave!". So I'm not one who says "Reconcile at all costs", or "Do it for the children". This just seems different. She's either a master manipulator, fooling a jaded person like myself, who has seen EVERYTHING, or she's truly in love and remorseful.
Like I said before, an affair is a bullet to the head of a marriage. She shot your marriage in the noggin, no doubt. You survived, a shadow of your former self, never allowing yourself to completely heal. Listen, there is no shame in saying, "I did my duty for my children. I did my best to keep the old drama from rearing its head all those years by burying my discontent, but it's time for me to go".
I just have this gut feeling that watching and waiting for a little while, with a healthy dose of skepticism, communicating with her, asking hard and pointed questions, and looking hard at the answers, is not unreasonable, since on the surface she seems to be remorseful and she never knew the extent of your mistrust and discontent, so she couldn't address it properly.
Regardless of what decision you make, I wish you love and happiness, and more importantly, you will have a ton of support here.