Scrant, Zues offers some good advice here. It's really important to keep working on that focus shift away from your W. Thing is, she has nothing good to offer you right now. It took me a while to realise that with my H, but it is true. What she could offer you right now, would not be what you want.
From all I have read on this forum, a couple of things need to happen in separate journeys. The LBS needs to overcome their longings (and codependent) behaviour and rebuild their own lives, get to a place where they truly will be okay either way. The WAS needs to fall flat on their face, realise OP isn't what they want and realise their new life is miserable.
Until both things have happened, I don't believe successful R is likely. Of course, you don't have much control over the WAS bit, but you can remove yourself from the equation and neither be friend or crazy ex. That part is easy (well...easy to get, but not always easy to do..) The other part is the you part. That part is about getting your own chit together without her in terms of parenting, finances, housing, work, friendships, social activities, health etc.
GAL helps with this a lot, and it is a case of finding GAL that works for you. It doesn't all have to be daunting stuff like Meetups - but to have enough going on in your life to shift focus away from your W, helps a great deal.
Take care xx
T 13 M 7 Me 48 H 46 SS 15 BD 7.14 PA D final 5.16 (H filed)
We receive & we lose, and must try to achieve gratitude & embrace with whole hearts whatever of life that remains after the losses - Dubus