I started a story like that once...the first line is literally "Married life is wonderful". ^^
The thing is, though, the main point of this story is for the MC to discover that they probably shouldn't have married their partner at all. ^^; That the two of them actually have a very surface-level relationship, which quickly loses its luster as society falls apart, and they start to lose the cushy lifestyle that distracted them from all their flaws.
Also, on their belated honeymoon, they travel to the place where the MC originally "died", and they're trying to decide if they want to "die" again, reversing the process and returning to their original identity...who would not want to be married and would probably just abandon their partner immediately.
...Yeah, it's a weird story. But technically the leads ARE married... ^^