Marriage isn't the end-point of a relationship. It's just a stepping stone, one aspect of a long-term evolution between two people who have, for whatever reason, decided to take a leap of faith and say, 'Well, hey, this is a person who I want to try with for the rest of my life.' Which is not a guarantee of perfection - far from it.
Do you enjoy holidays with your family? I don't mean your mom and dad family, but your uncle and aunt and cousin family? Personally, I do. There are several reasons for this. First, I am very interested and fascinated by how everyone loves each other, but no one really likes each other. Second, the fights are always the same.