Honestly nobody should get married to someone with incompatible preferences regarding coffee ;-) This is also the beauty of the aeropress or paper cone method: you make your own coffee, everyone else can make theirs or not. And when I make the french press too strong, I'm happy to drink the whole thing myself!
And the price to the environment, and the price to a relationship unable to handle a minor disagreement? Perhaps you haven't considered all the factors at play.
I'd like to see the breakdown on KCup usage in the home versus in the Office.
The majority of K's I've seen are in the office, where you're looking for simple streamlined solutions to keep people from bitching about the surrounding environment, and get back to work.
I think most people in a relationship can deal with the morning coffee differences