Yes - it will be a hard and long process. I am not there yet, but I fear that the day will come.
It will be less painful for the kids if at least one of you remains calm. If it comes to it as long, and as the terms are fair, then agree the terms and just get it over and done with. You may R in the future (if you want to) but if she is set on D now, then you have to just get through it.
Do not quibble over stupid things. I have known couples quibble over who pays off the last $100 on a credit card. If it is immaterial - let it go. I don't mean let her walk all over you. But be fair. The things to remember are (and this is applicable to multiple situations): am I doing X because what she is asking is fundamentally unreasonable, am I doing X out of spite; is X in the best interest of the children and how does doing X help me detach.
(BTW - I ask myself those four questions all the time, and I still sometimes do the wrong thing)
You will gain some self-respect and your kids will be better for it in the long run. Eventually your W will respect you too.
