In a lucid, bracing and much-discussed essay for Oprah.com called "The New Midlife Crisis," author Ada Calhoun sums up the reason why so many members of Generation X — especially women — feel stressed out and stretched thin: money.

"By some estimates, we carry more debt than any other age group (about $37,000 more than the national consumer debt average). We're some of the best-educated women in history, and yet we're downwardly mobile; about two-thirds of us have less wealth than our parents did at the same age," she writes.

And individuals aren't to blame. "This isn't because we spent too much on Pearl Jam CDs," writes Calhoun. Prices have gone up for everything that matters, while wages haven't followed suit.

"The cost of a home has increased by more than 80 percent from 1970 to 2000, the last year for which data is available. (Between 2000 and 2005 and since 2013, home prices have outpaced salary growth.) In the late '70s annual tuition for a four-year college was less than $11,000 in today's dollars, now it's three times that."

In consequence, she points out, "40-somethings haven't saved nearly enough for retirement. More than half of unmarried Gen Xers have less than $50,000 saved."