Here's the good news: that cabin's not walking away anytime soon. Limited number of takers for somesuch, and skittish lenders. So you have some more time to think.
Does selling your house get you there? (And I told you, buy some crap particleboard and paint it and you won't lose a dime). How big's the gap? Could you legitimately work as a "consultant" for your existing job at a set price or get a similar part-time job there enough to qualify you for a smaller mortgage? (ironically, you are the reason that subprime mortgages were first invented -- to provide people whose income might be sufficient but not steady an opportunity to own a home. The idea was that you could pay in different intervals at different rates. Because it wasn't 12 even payments, and that was harder to package, you'd be subprime).
Don't sell the piano, I think. That's something you'd regret later. (I saw that movie and all. Even with the finger missing, it was bad.) And I just choke on cashing in 401ks for anyone over 40. But then, I lack imagination.
Is there anything you could do for the next few months to make enough extra to fill the gap? Tend bar at a strip joint? Play the piano at a brothel? Strip at a nursing home? (they confuse the $5s for $1s).
Finally, and perhaps less palatably, you could borrow the money from family. Doesn't have to be on love and faith return either. You could give them a proper mortgage interest, or a few of your acres for a nearby homestead. (Actually, I see you in a family business somehow. Maybe they run the B&B, and you're the crazy farmer they tell the tourists to stay away from?) But if you sell everything you own and end up with only the house, what're you going to do to live? If you really want to farm you need to clear the woods, buy seed and equipment. Better factor in that cost as well.
This is so the right thing to do. Life's all about doors closing and windows opening. (By the way, I never believed "things happen for a reason." I believe that things happen and that it's our job as humans to make it reasonable. You will.)