Has the institution of marriage become obsolete?

Sandra Tsing Loh's piece in the Atlantic Monthly laments the twilight of marriage and divorce during middle-age. Expectations must have been out of scale for many American women who thought they could have domestic stability coupled with prolonged teen-style romance with the same man over the course of 20 plus years. 

Based on the math, the author and her friends married in their mid to late twenties, following tightly a domesticated, heteronormative script.  They bought into it but now they are bored and sexless in their mid-40s. Of course, the alternative of delaying marriage, or foregoing it altogether, would have excluded the option of childbearing, or diminished the odds of conceiving, an unknown path that ventured too far from the fantasy myth of domesticity.