Utter nonsense - is marriage to some people voluntary slavery, where every thought word & deed must be shared or approved ahead of time by another?   
The term "Marriage" encompasses such a host of different interpretations and expectations! And legal obligations! No wonder far fewer people are getting married. 
Not all that many decades ago marriage was an economic & social necessity for men & women both - people married people they had known in their neighborhoods or small town growing up; or they married near-total strangers on a romantic whim. Most assumed marriages would last forever & it was a disgrace if they didn't. Mail order brides were still a very active piece of Alaska even into the 70s. 
Has anyone noticed the world is changed?
Thanks to globalization & instant communication – or miscommunication – marriage today is a 50-State nightmarish legal paradox; a sentimental carryover of custom; and a passing economic anachronism. New economic & romantic mating models will emerge