RiceDrift, I think looking at the end of your last response you've answered your own question (ie letting her go). You talk about her hopefully 'changing', but we all know she won't, she will only get more resentful and even suspicious of your wanting to take off. Us women always talk about 'men changing' etc after marriage, but it goes both ways.
If you have so much money, buy a SMALL place and go from there, use the money to ease off work, maybe freelance in whatever you do, and go on short trips. They're extremely satisfying. I myself get bored travelling on my own- I can't travel for more than say 3 weeks at a time before I want to head home. Not because of homesickness, but just for the freedom of not living out of a bag, being messy again, my own bed and shower etc. And I am always extremely well planned and organised as to what I want to see and do so I don't feel the need to go off on extended trips anyway.
Good luck with your decision....and at this point I want to say I really wish I could find a guy as free as you to travel and work overseas with, though they're all much younger than me and taken :(.