I agree, an ultimatum on childcare and housework is in order here.
He has to take it on, which will save money, and ease your burden. He actually sounds like a total arse actually. I'd hate him for all this stuff,
There's no reason why he can't put the dc into childcare if he needs to arrange interviews etc, but if he's not even getting these, there's absolutely no reason at all for full time childcare bills.
Thing is, the longer he's without a job, the harder it'll be to get one.
That's where i'd start. He was all great and powerful issuing you ultimatums, now that the boot's on the other foot, it's time for him to see how that feels.
His comments about his 7 years of misery are utterly shit. He had 7 years (apparently
) so you have to suffer for the rest of your life?
Remind him that regardless of anything, you are making a go of it, and could leave him and live independently, so he needs to sort himself out or admit he has to reassess the decisions he's made.
If he's not careful, whether or not he gets a job, the attitude he's demonstrating is likely to end in divorce anyway.
Keep posting. Do you have RL friends out there?