Relating to your romantic partner daily can be challenging. There's always something to do like groceries, cooking, cleaning, and taking care of the kids. Needless to say, some of these chores aren't the most fun.
So it definitely helps when one or both partners have a good sense of humor. If you can laugh together, life doesn't seem as hard. And these girlfriends and wives sure make their partners' lives a little brighter, ha, ha.