The WAS only sees the past never the present in our situations. They cannot accept us for who we are now and sometimes I believe they are angry at us fo waiting so long to change.
I feel that is where my W is at right now, angry that I waited so long. Angry that I did not know how much pain she was in and change myself so many years ago. But as you said the past is history and I can only deal with stuff from today forward and that is what both of us are doing.
I also feel that after the D their anger disipates and they see the LBS in the present and resent the fact that they did not see it while they were M. I wish your W could see you for who you are now as I do my W.
I'm her for you my friend. All will work out for you and your kids as long as you keep your emotions in check and let her chitt be her chitt and not yours.