Why are marriage rates at an all time low? According to this article the biggest reason is men’s desire to be financially stable prior to marriage and women’s desire to marry men with jobs who have that financial stability. Those with a higher incomes and higher educational attainment are more likely to marry and less likely to divorce. [read_more] As fewer and fewer men without college degrees are able to find work, fewer of them marry. As for why Gays have pushed to be legally married,
If you view marriage as aspirational, as a milestone that Americans are sidestepping because of financial insecurity rather than disinterest, of course it makes sense that access to marriage should become more, not less, desirable over time, especially to historically marginalized groups. Marriage is, increasingly, a status symbol.
More on declining marriage rates, and the reasons for it, with many charts and graphs at Business Insider.