As Chekhov put it, “If you’re afraid of loneliness, don’t marry.” He might have been on to something. In a review of two national surveys, the sociologists Natalia Sarkisian of Boston College and Naomi Gerstel of the University of Massachusetts at Amherst found that marriage actually weakens other social ties. Compared with those who stay single, married folks are less likely to visit or call parents and siblings—and less inclined to offer them emotional support or pragmatic help with things such as chores and transportation. They are also less likely to hang out with friends and neighbors.

Single people, by contrast, are far more connected to the social world around them. On average, they provide more care for their siblings and aging parents. They have more friends. They are more likely to offer help to neighbors and ask for it in return. This is especially true for those who have always been single, shattering the myth of the spinster cat lady entirely. Single women in particular are more politically engaged—attending rallies and fundraising for causes that are important to them—than married women. (These trends persist, but are weaker, for single people who were previously married. Cohabiting couples were underrepresented in the data and excluded from the study.)

Sarkisian and Gerstel wondered whether some of these effects could be explained by the demands of caring for small children. Maybe married parents just don’t have any extra time or energy to offer neighbors and friends. But once they examined the data further, they found that those who were married without children were the most isolated.