Frank,
In rereading all of this I realize you've already made the decision, since you can't take it with you my advice is to find a young couple who is looking for a sailboat and give them the deal of their lifetime, along with technical advice as long as they still own the vessel.
I stopped surfing a few years back, 45 years of riding waves, but I can sit in a chair and in my mind's eye I can see everything, the shape of the wave, the speed, the flying foam, the sunlight sparkling off the ripples like a million diamonds, and I find that that's enough to get my heart pumping.
So cut the cord Frank, cut it with joy, cut it with a sense of accomplishment, send your baby out into the world, she will live in glory in your memories.
Then you get the motorboat!
Aspera ad astra,
Tim