when you say "wife tried riding" do you mean that she was basically new to bicycling and was riding this bike as her intro to riding?
when you say "did not enjoy it" do you mean that she was not comfortable and at ease with the handling and geometry of the bike?
when you say "rode six or seven times" do you mean that she took it out around the neighborhood or to a trail a few times and felt uneasy with the bike and unsure of how to improve the ride so packed it in early?
or maybe you truly mean that she happened to buy a bike that maybe didn't quite fit her or suit her riding style or realized that her bum knee wasn't going to allow her to ride more than 15 miles at a go anymore.
::shrugs:: this ad just strikes me as someone who probably got matched up with the wrong bike for what they wanted to do and/or didn't know how to build up their riding skills.
I wish more people could avoid making the mistakes that put them off riding forever. Bike shopping is way harder than car shopping, but there's a lot less (reliable, unbiased) guidance for it.
All that said, sorry OP, it's late and I'm just kind of posting the rant and rhetorical questions in my head right now. Best of luck selling the bike. It looks like a fun ride to me