I am going to echo everyone else and say that Snodderly is right.
I remember, while I was away one weekend, my STBXH, was supposed to be staying with S, and ended up accepting overtime at the last minute. It was then MY fault that there was no one to stay with S, because I was out of town and had left him to be a responsible parent.
When I told him it was his S too, he said that in the past, it was different because I wasn't out having fun, I was either working or something, so it was ok for him to have to handle it then, but since I was now living my life, it was all my responsibility. Which I found to be hilarious in a twisted sort of way.
Another day in the life I guess...
"Acceptance doesn't mean resignation. It means understanding that something is what it is and there's got to be a way through it."--Michael J. Fox