I don't have children, so I won't comment on the specifics, but as far as the more general issue at hand here...
He wants control. He wants the world to bend over backwards for him and his whims. It's as simple as that, really.
In my case, XABF managed to isolate me from everyone else - my family, my friends, and he was working on my job next - so that he'd have full control. It had nothing about me being unreasonable, and everything about him making things so difficult for me that I would finally cave in and give in to what he wanted, and become more isolated. It was bad enough when he was reliable with his own plans, but as the alcoholism worsened and his health went downhill as a side effect all those plans were constantly being cancelled, as well.
You made the plans, the kids want to stick to the plans, so stick to them.
He's going to complain and scream and yell, so let him.
To quote Macbeth out of context:
...but a walking shadow, a poor player,
That struts and frets his hour upon the stage,
And then is heard no more. It is a tale
Told by an idiot, full of sound and fury,
Signifying nothing.
(It seemed fitting. *grins*)