Op,
You essentially forced him into making a theoretical decision on the basis of our own insecurities, when there is absolutely no job on the horizon at all, just the wistful longing of a middle aged bloke in a band.
A middle aged bloke in a band, who, let's remember, has already left one international band and come home to the uk because he missed his kids.
He isn't going anywhere.
Not unless you chase him there with your constant needy insistence that he makes up his mind here and now about a situation that is unlikely ever to arise.
Get some perspective and let the man dream. He's not going anywhere.
But you know, you could always encourage him and help him fulfil his dream and make it a huge family adventure, if you wanted to. It won't just come up out of the blue.
What are you afraid of?
A 2 and a 5 yo can be schlepped wherever you want them and you can have a whale of a time.
And yes, I've spent plenty of time away from dh, both in the uk and out of it. With the 3 kids. I could understand your anxiety if the situation was even a possibility, but you forced the man to make a decision about nothing. I've spent plenty of time worrying when dh is away (or going away), but your dh isn't even going anywhere.
You are being melodramatic and hysterical about nothing. A situation you engineered yourself.
Let it go.