Here’s an interesting study/history on the status of marriage.
How Marriage Became Optional: Cohabitation, Gender, and the Emerging Functional Norms
J. Herbie DiFonzo Hofstra University – School of Law
Rutgers Journal of Law & Public Policy, Vol. 8, No. 3, p. 521, Spring 2011 Hofstra Univ. Legal Studies Research Paper No. 11-29
Abstract: In 1960, two-thirds (68%) of all Americans in their twenties were married. But by 2008, just over one-quarter of twenty-somethings (26%) were wed. According to the Census Bureau’s American Community Survey, married-couple family households constituted only 49.7% of all households in 2009. The Census Bureau reported in 2009 that 96.6 million Americans eighteen and older were unmarried, a group comprising 43% of all U.S. residents eighteen and older. Children’s living arrangements have also undergone substantial change. In the past generation, the percentage of children in the United States who live with two married parents has markedly declined. Although our culture is still ambivalent about families not based on genetic ties, social acceptance of a wider range of family forms has increased. This multiplicity of family structures means that marriage has become an optional arrangement for creating a family. How did this happen? And where is the American family headed, in both cultural and legal terms? This Article sketches out a framework for analysis of this central social question, and argues that family law is moving in the direction of adopting functional norms for determining family composition and adjudicating family disputes.