Ok. This demands a robust response. I ride a 700c Highracer, and a 20/26 (and have audaxed it), having given up on my lovely Giant Defy - or more accurately, the pains resulting from riding audaxes on it.
https://www.flickr.com/photos/51992734@N06/36282391815/in/album-72157686993318525/FWIW, you'll never convince her - my wife sounds very similar to yours, and she doesn't like me riding a recumbent either. Converting her Trek to electric recently may have quelled some of the objections. But I've not yet played the trump card - she fell off a horse 3 weeks ago, resulting in 5 broken ribs, concussion, a hoof-sized angry bruise in the small of her back, 4 days in hospital, a missed holiday and a missed bridge tournament. She can't yet drive as she can't change gear with her left hand, so can't go out unless I drive her. And we are dog-sitting, so that's all down to me as she can't hold a lead and walk the dog (3 times a day). And I can't go out on a bike in case there's a problem and neither of us can then walk the dog. Or go flying my model aeroplanes. The day of reckoning will follow. Revenge is a dish best served cold they say.
So, taking the objections in order:
Why are they unsafe? You've less distance to fall, it's very unlikely you'll go over the handlebars so a broken collar bone or arm is equally unlikely. You'll get road rash, mainly on the thigh and elbow, but some elbow pads will mitigate that. I get more consideration from other road users on my 'bent than I ever got on my DF bike, mainly because of the rarity factor I suspect. Use 2 lights on each end (flashing and fixed) and don't listen to the radio etc. via earpieces. Keep listening at all times, and get some good mirrors. Kim will no doubt be along shortly - she had a big off recently but the consequences seemed to be mainly road rash.
Why are they stupid? That's just an even more stupid (pls excuse me...) assertion. What aspect of a recumbent is stupid? Low IQ? The colours?
Why are the riders stupid? I don't like football (even though my daughter played Premier League soccer and internationals for England) so I don't go with the majority, does that make me stupid because I don't ride a DF like 99% of the cycling population?
Get one anyway. Maybe a 2nd hand one to learn on so the costs are minimised. You'll fall off a few times, so get some elbow protection, wear sleeves and maybe longs to start with, and a helmet, and find somewhere quiet to practice until you can start and stop confidently. What you will do is improve your lower body flexibility and your cardio- fitness, or at least keep it up. Not to ride at all is the way to an early grave.
Go against the flow. Go recumbent and get used to the face-ache from grinning at the thrill of the comfort and new perspectives - you'll look ahead at the scenery, not at the tarmac a couple of metres in front.