You tend to catastrophize. Him leaving will not kill the kids. Yeah, he may well have them convinced that, of the two of you, he's the cool one. They're kids; what do they know. But go ahead and let children make major adult decisions, if you think that's how you want to roll.

I'ld go right along with that proposal he made regarding the dog. See how long that lasts. My bet is that you will end up with doggie right there under your roof, without you having to say or do a thing. You keep forgetting: this guy hates responsibility. If he ever gets out of your house, you probably won't see all that much of him. He'll be busy hanging around the next woman who supports him.

The paperwork about school was left around to get a rise out of you. You took the bait. Get this whole mess into family court, and let the judge decide if your daughter can study where you think she'll do best.