Every time, when a new RPG comes up, me and my husband end up asking ourselves "Can we play this together?", and mostly, the answer is more than disappointing. Either you can't, or the coop experience is that bad that you don't want to try it.
And now, DoS appeared, shiny, good looking, and offering a dual-coop experience we did't even expect to see. Dual Dialogues, the interaction with the environment, and that you start with two equally important main characters... even if the game isn't huge, even if the story isn't that great, this is just what we wanted...
You're very lucky.

I've been married for over 30 years (and playing on computers for nearly as long) and I've still never been able to get my wife interested in playing RPGs.

I can see why you'd be enthusiastic about the coop aspect. Even if the story turns out not to be as good as it might be, playing as a duo with your partner would be a lot of fun. Colour me just a little bit envious.....