Well the drive home (30-40 min) was hell. She pounded me with all my failures and she wasn't to go down with a sinking ship. After 15 min, I sternly say stop..enough! I know I have failed to keep promises, I failed to pay bills, I have failed to have loved you the way you deserve, but I can't change that. I wish I could but can't!!! I go on for about 10 minutes not about wanting to get back, but telling her that I will not allow her to try and break me down or continue to remind me of my past failures and that I am taking the steps to rebuild myself up for myself and my boys.
Wow, all that was in front of the kids? She needled you into it. You will have to be the one to stand up to her about not discussing personal matters in front of the boys. She is just a barrel of emotions, so she will blow whenever she feels the need, even in front of her children. This is showing the boys that their family is threathened, and it's scary. It also shows them what a man does when a woman attacks him (verbally). They are watching you to see how you handle this, and will probably teach them how to apply it in the future after they are grown.
My advice for now is to not include her in family outings (at least for a while). If she tries to invite herself or asks to go, I'd say something like, "Considering how things went the last time, I am not in favor of it". She wants to live a separated life from you.......so give it to her. I especially discourage any more rides together in the same car. That's a slaughter waiting to happen.
Strangely enough, when the WW thinks you are no longer interested in her, having her around, spending time with her, etc., it causes her to want to draw a little closer. That's why many WW's will turn on the charm just long enough to make the H think there could be hope. Once she sees he is still very interested in being with her.......she pulls away.
I believe you will need to set some personal boundaries. Read the link in Cadet's list.
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!