When I commented a couple days ago, I had the sense that you were resolute in your intention to D and that your plan out of infidelity was pretty sound.
Now it sound like you have since wavered from that plan. You went through confrontation and, seemingly, your WW picked you. "Yay, Pick Me Dance, over!"
She gave you the song and dance, "I never wanted to leave you", "I only ever really loved you", "I'm sorry" blah, blah, blah...Followed by some crumbs of NC letters, promises IC, and tears of self pity.
Yet you set forth boundaries. Which is just like saying, "I won't divorce you if you do the following..."
You've shown her that you aren't serious, and that so long as she acts like a remorseful WW she can still have her cake. You gave her a plan to be in self preservation mode.
I will tell you that I experienced all of what you experienced. Almost EXACTLY.
Yet here I am, nearly 4 years post D-day, almost 2 years post divorce.
I get that you want to save your marriage. No one wants to put their family through the trauma of getting divorced. I think nearly everyone here fell hook, line, and sinker for the WS song and dance.
And for some WS's, they probably meant it at the time.
But, at least for me, not so long after all of this and you're getting comfy thinking that you're R-ing, things go south. You're both supposed to be working on your own sides. You working to heal yourself. And your WW working to fix herself. But she's also supposed to be helping you heal. She is the one that destroyed you and the marriage, right?
What often ends up happening, again based on my experience, is that the WS usually gets too caught up on their side. They get too bogged down in their self pity and self hatred and "woe is me" and "I'm awful, what's the point?". They get so stuck that they can't help you. And you probably need more help than them. You're the one with the gaping gunshot wound to the chest. They're just awash in shame from having the best naughty sex of their lives and getting caught.
My point is, don't let your guard down. I'm saying this with the assumption that you now really want to R and you think it's possible.
I'll tell you in the almost 4 years since I've been on SI, I haven't seen it happen. I know there are only a few members here that I've read about in "SI Lore" that made it through the tough process and succeeded. Walloped and MrsWalloped come to mind. But they are definitely in the very small minority.
So it is possible that you can successfully R. But what I usually read about is the WS either unable to handle their side or just giving up altogether, both the BS and WS. For the BS, the A was too much. It was a dealbreaker after all.
With D, the marriage may be over. But your relationship with your isn't WW necessarily over. You get the closure you need. If she is truly remorseful, she would give you the divorce that you ask for, no questions asked.
You get your time to heal and move on. Then maybe after some time, if she's really worked on herself, you could try a fresh start.
D shouldn't be used as a tactic to get your WW to come around to the marriage. I tried it. I got similar results as you. Yet some time later my WW went astray and here I am. It won't keep her in line. Only acting like a good wife under threat of divorce won't really change her. She'll just go through the motions until you back off.
If you really want to D, then forget about boundaries and trying to enforce them. Hard 180 and detach and only talk about D and kids.
If R is still in the back of your mind, stay vigilant. You're looking at 2-5 years of constant effort and work from her before you can call R successful. No guarantees, even if she does all the work.