Does misery love company, or does misery make company equally miserable? Psychologists have long pondered whether couples and close friends are depressed in tandem because one person's mood poisons the well, or because people gravitate toward significant others with the same traits.
In the first longitudinal comparison of mood in romantic partners and roommates, Chris Segrin, a professor of psychology and communications at the University of Arizona at Tucson, found that emotional tone is set at the starting gate.
Segrin surveyed 153 dating couples and 170 pairs of roommates for three months. He concluded that women's emotional states—positive or negative—were unrelated to changes in their boyfriends' moods and vice versa. Moreover, couples that had been dating longer were no more likely to mirror each other's emotional states than were newly minted partners. "I was surprised by how similar the partners' moods remained over time. I thought there'd be much more fluctuation," says Segrin.