I see a lot of myself in your posts. You cannot change the things you've done wrong (I wish I could) but you can stop doing more things wrong.
Stop doing ANYTHING for her. I keeps you stuck in a pattern and enables/makes her choice easier.
The kids may open up to you more because they feel safer/at ease with you. Mine did (and do?). Par for the course.
I got the lion's share of the bills too.
Nice guys finish last.
But we finish.
"Fear is the mind-killer" Muad'Dib Me 53, XW 44, DD 14, DS 12 Bomb and OM 12/15/06 Separated 01/02/07 Divorced 05/13/08 X married OM(OMH) 08/2009 Married 06/09/13