BTM - I'm new to your posts, but sort of caught up. I would guess STBX feels like she's failed in your relationship 2x now and that she cannot face or find the energy to go through reconciling again and possibly failing again. I wouldn't take it as not caring or missing parts of your life together- she's clearly very broken inside and trying to distract herself with a new man/new life.
Stay strong and believe in yourself - you're clearly doing great things for your D and showing her positive relationships that she can use as guidance for her own someday.
I don't think she feels that she failed at all. I think she believes she is entirely justified in everything she did, so therefore, no failure on her part. As for being broken inside, that I agree with. Again, she feels she is the most well balanced person out there. She isn't distracting herself now, in fact, her life here at home with kids and I was a distraction from what she really wanted for years. OM/boss is all she ever wanted. That and a life of freedom and not feeling controlled by anyone.
I recently realized that the one thing she thrives on is the constant battle for power in the workplace and in her love life with OM. She often says how stressful it all is, but for some reason she needs that to live. She can't be happy in a calm, peaceful, "ordinary" life that most of us strive for.
I am staying strong and believe in myself more than I ever have in my entire life. The man I am today is a much better one than the one I was 2 years ago. It truly is a shame that STBX has chosen not to be with me now. But, at the same time, I actually understand how tough it must have been pining for him for so many years and that she could have never chosen me over him, once she was close to her holy grail.
I have said this a lot lately, but the more I understand the whole thing, the more closure I get and the better my future becomes.