I fear my W will hear " who are you going with, where are you going and why?" Not my intended subject matter.
I guess I just have to act "as if" it will all work out and take it from there.
Your instincts are correct, and I think you're dangerously close to re-attaching, and you know better than to jump on that train. You know the futility of caring about the where or with whom. Your only legitimate concern is the money.
I can't advise you on the money aspect. In my case, I had the money discussion last month, set that boundary, and hope not to have to discuss it again. If money's tight, that might be about all you can say. [in a non-lecturing way, and not in the context of any mysterious trip]