I agree with KML and Mr. Bond. Stand firm now, and kick his ass back to reality!
I am so sorry that you're going through this. But that's why we're all here on this board, we're going through something with our spouses and are here to stand in your corner and support you.
I agree that you need to secure some funds now if you can. It's quite the norm that and MLCer will wipe out insane amounts of money and not blink an eye doing it. Been there done that.
It sounds as if you two do have a solid relationship and good communication. If he sees you as the "rock" and he's a high energy kind of person, and you usually always come to decisions together, IMO I would think he figures as long as your ok with his idea for this flight of fancy, then it really is ok.
NOW given with some people it is! But if it's not, then don't stand for that crap. Geez Im even a little baffled at his behavior because I get the idea he's quite a stable person.
But that's the thing about MLC. It hits and a stable person becomes very unstable. An unstable person becomes practically insane. Big personality changes.