This shit is all very scary and confusing to you right now. You're about to walk the plank into the unknown. This will be the last "principled" career decision that you make up until the point that I'm writing you this, and you will learn a hell of a lot from it - about yourself, about your marriage, and about life in general. Shit's about to get really difficult for you, in a way that you sense now, and that's why you were up unable to sleep at 3am last night.
There will be no gentle landing, and that hail mary pass that you're hoping to connect with that idea of yours isn't going to connect, at least not as neatly as you need it to. And certainly not as quickly as you need it to.
I'm writing you now to let you know that it's going to be alright. You have this cocky hunch that the move you're making is going to be the best move you ever made, and it will be, mostly in ways that you can't really get yet. But you're going to pay for it, too.
The investment that you're making now and over the coming years is going to come back in a big way. Don't let knowing this make you work any less hard though - it's only under this pressure that you get where you need to go. It's only by putting more time into something that's more difficult than anything you've tried to do before that you get where you need to go.