It's the same reason I want to beat Elizabeth Wurtzel with an old shoe. They're part of the same cabal of disillusioned essayists making a woman's middle age sound like hell on earth. It has been clearly explained for me by 25-year-old Irina Aleksander in the New York Observer piece "The Cautionary Matrons":

Single 40-something women warn us about being too career-oriented and forgetting to factor in children; married women warn us that marriage is a union in which sex and fidelity are optional; and divorced women warn us to keep our weight down, our breasts up and our skin looking like Saran Wrap unless we want our husbands to later leave us for 23-year-olds.

Essays written by Cautionary Matrons are one of the few genres dominated by our gender; Laura Kipnis' Against Love: A Polemic and Cristina Nehring's A Vindication of Love, which landed on the cover of The Times' Book Review, also come to mind. Not that men are strangers to personal narratives, of course. (snip) But while men tend to be cheerfully self-deprecating, women are downright apologetic, asking themselves what they've done wrong and how to fix it.