eod, sailboats aren't just "point and shoot" or drive 'em like a car. they are constrained in how they can move by the wind and waves, and sometimes you can literally spend hours under full sail gaining only a few hundred yards. Or, losing miles.
The transition from a wheelchair to a cane or walker also might not be good enough on a sailboat, where there can and will often be constant motion in mutliple directions, and even able-bodied seaman with all four limbs expect to get tossed around from time to time.
Not to mention, you'd need a ship (not just a boat) to get enough flat space to simply put a walker down with all four corners on the same "floor".
That doesn't mean you (singly or as a couple) can't enjoy sailing from time to time. Just that long passages on regular schedules aren't going to be at all practical, especially when you are basically single-handing.
There are plenty of places to get started with sailing lessons in Chicago. Sign up this spring, try it firsthand and see what it is all about. Fun? Yes. Hollywood? Sure, like a six-shooter that fires a hundred bullets without reloading and dead men who don't bleed.
Get a small enough sailboat and the whole thing is a walker! There isn't a single spot on my 30' where you can't hold onto solid objects in the cabin. But, it certainly can toss the most able bodied folks around. Lake Huron and Erie in particular can build extremely nasty seas in the blink of an eye.
A bit of personal background: My uncle had been diagnosed with terminal brain cancer and given 6 months to live. We had a tradition of chartering a 35' sailboat every year, and he was very firm that he still wanted to do this. The tumor had just begun to alter his vision and motor functions. We sailed Lake Huron and even made it into though the locks to Superior all the way to Whitefish Point. It was not all easy, and there were many times he fell, lost grip, and bruised himself on the boat. Particularly when we hit some 10' swell rolling across Lake Superior. We did it, and I am very thankful we got to spend this time, however it was borderline possible even in the early stages of his condition. He ended up living a year, but the last 6 months paralyzed and almost blind. He was still able to walk with full strength, albeit slightly impaired. I can't imagine that trip being possible (with 3 other able bodied adults on board) at more advanced stages. Seafaring is a personal thing. You must be willing to accept the challenges, become a jack of all trades, and accept the consequences. I would hate to hear of another story of people getting plucked from a perfectly good boat because they couldn't cope with the conditions. The trip you describe will expose you to months of weather, currents, fog, ships, hurricanes. These decisions should not be made lightly.
Whitefish Point, August 1999