Games for non-gamers

Borderlands! My wife is also.a non-game, but she absolutely loved the characters in the series. Maybe similar enough gameplay to COD? Whatever you do...good luck! The struggle is real!

Yes, something with strong characters in it, as opposed to just a lot of action and anxiety.

Stardew Valley! It's retro styled, super relaxing but surprisingly deep. I think she'd love it, and if she doesn't then you've eliminated a pretty huge category of games which would help find what she does like much quicker. It's a win-win and even available on mobile now. 

As far as co-op, Borderlands 2, Far Cry 4, Sniper Elite 4 and Unravel 2 ( Co-op puzzle platformer)  are all pretty fun playing with someone else. I used to love flying around the map in Far Cry 4 with my girlfriend looking for outposts/base to liberate or infiltrating a base while one of us on a rampaging elephant and the other in a gyrocopter wreaking havoc on the the entire outpost. Borderlands 2 is also an absolute blast with friends.

fall guys, sims 4 or char driven rpg like red dead or witcher, mass effect etc......

Cant go wrong with a open world survival game, recently been hooked on Subnautica once more.

I mean it's not a FPS but Portal was always a fun one to play couch CO-OP on. Though it has been known to test some marriages lol.

For cooperative games, I would recommend It takes two, Portal 2, Degrees of Separation, and Cuphead 

gamers

It's take two is nice game.