Review of Going Solo: The Extraordinary Rise and Surprising Appeal of Living Alone by Eric Klinenberg, a sociologist at New York University:

alone in the dark

“…[S]ingle living [is] not a social aberration but an inevitable outgrowth of mainstream liberal values. Women’s liberation, widespread urbanization, communications technology, and increased longevity—these four trends lend our era its cultural contours, and each gives rise to solo living. Women facing less pressure to stick to child care and housework can pursue careers, marry and conceive when they please, and divorce if they’re unhappy. The “communications revolution” that began with the telephone and continues with Facebook helps dissolve the boundary between social life and isolation. Urban culture caters heavily to autonomous singles, both in its social diversity and in its amenities: gyms, coffee shops, food deliveries, laundromats, and the like ease solo subsistence. Age, thanks to the uneven advances of modern medicine, makes loners of people who have not previously lived by themselves. By 2000, sixty-two per cent of the widowed elderly were living by themselves, a figure that’s unlikely to fall anytime soon.

What turns this shift from demographic accounting to a social question is the pursuit-of-happiness factor: as a rule, do people live alone because they want to or because they have to?”  (via The New Yorker).