I feel like I just want to run out of the house and not stop running.
If it is causing you to want to react to what's going on in the household, then after years of that kind of stress.....your W must have felt that she needed an escape also. She did not choose a positive escape, needless to say.
So, did you get the computers, etc. put together or will you have that to face when you go back home? I'm wondering if your W always had to do the jobs that the kids needed done, the house, etc., b/c you got too stressed over that sort of thing. Or.....is it just now?
Realize that the holidays will not be an easy time. Prepare ahead of time. Talk to your kids after grandparents leave and tell them that it is going to take you & them working together as a team to help each other get through this season. Do they do as you tell them or do you need the "Nanny" to go get your home in control?
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!