Marital Problems May Ultimately Stem From One Thing We All Struggle With: Our Egos
I took a read of this story and think there is a good bit of wisdom here. The main point of the book discussed is that often couples will have “separate, individual egos trying to get along with each other.” But that's the opposite of what marriage is supposed to be.
Marriage is a full-on union of two persons who then become one unit. These two are still fully who they were before, but at the same time they are together a new creation through the vows they make at the altar. Everything must be handled in light of that change, and if it's not, if it's handled as if the two are merely roommates or bed-mates, there won't be proper functionality.
Simply put, we need to be humble in our marriages, and lay down our desires in exchange for our spouse's interests. When both husband and wife do this, it creates an incredibly satisfying relationship for both of them.