Hi Dave, a good question on the trike. Unfortunately, they cost a lot, of course I am speaking as a former Gold Wing owner, whether it's Honda or Hardley. Finding a used one can take some doing. Hual's Trikes on Hwy 29N, about 3 miles south of Cantonment, had some out front when I left, they deal in new ones and used/trade ins.
There are a few other choices but they look kind of chintzy, just about any cycle magazine will have advertisements for them in the back and the cost would/should be lower than getting a full blown one as mentioned in the first paragraph.
Hopefully you'll find her one, in the right price range, I wish my wife would have been more "accepting" of the back seat of the ride, but she pretty much let me get what I wanted for myself to ride so she's been a keeper there. Since she doesn't ride ("or passenger"???) it was the main reason I went ahead and traded the Wing in for the Mustang.
Good luck,
Dennis
...still living in a tent, at least the food is good.