Sorry you're having a hard time of late. I went back and read up on your sitch today. Is there any way to have XW share some of the financial responsibilities? I saw that you cosigned for her new car, are you paying anything for that? If her name is still on the mortgage then she should be contributing.
I know it's difficult. All I can say is hang in there. Try to keep up PMA. You're doing a good job with D5. So you forgot one thing, big deal! No one is perfect. Just forgive yourself and start fresh tomorrow.
If you love somebody, set them free. http://tinyurl.com/2empx2g