We change after we start dating, study suggests

"The results confirm what most friends complain about -- romantic partners are a distraction from friendships," said Brett Laursen, Ph.D., one of the authors and a professor and graduate studies coordinator in the Department of Psychology at Florida Atlantic University. "It also is a stark reminder how the peer social world changes during adolescence. Same-sex friends become less important and romantic affiliations become more important."

Similarity is the hallmark of adolescent friendships and not coincidently, most single adolescents report friends to be among their most important relationships. However, the start of a new romantic relationship alters the balance of close relationships. As romantic relationships surpass friendships in terms of importance, adolescents are inclined to change to become more similar to their romantic partners, even if it means that differences arise with friends.

"Much attention is given to the role that friends play in the acquisition and reinforcement of health-risk behaviors," said Laursen. "Adolescents rarely drink alone, so concerns over peer pressure to experiment with and abuse alcohol are well placed. Often overlooked, however, is the fact that initial involvement in romantic relationships tend to coincide with initial exposure to alcohol."

In the first part of the study, participants (662 girls, 574 boys) ranging in age from 12 to 19 years, nominated friends and romantic partners, and completed a measure of alcohol abuse. Friends with romantic partners were less similar on rates of alcohol abuse than friends without romantic partners, especially if they were older and less well-liked by classmates.

The second part of the study focused on a subsample (266 boys, 374 girls) of adolescents who reported friendships that were stable across two consecutive years. At the outset, neither friend was involved in a romantic relationship. Using this longitudinal subsample made it possible to measure changes in friend similarity for those who did and did not begin a romantic relationship.

Similarity between friend reports of alcohol abuse declined after one or both of the adolescents became involved in a romantic relationship, to the point where they became more similar to their romantic partners than to their friends.

Levels of alcohol consumption did not differ for adolescents with romantic partners and adolescents without.

"The findings suggest that participation in a romantic relationship does not elevate the risk of alcohol abuse beyond that involved in participation in friendships," said Laursen. "Instead, it is the source of the risk that changes. Friends no longer shape drinking habits the way they used to. Romantic partners now dictate terms. Your friends were right: You aren't the same person you were when you were single."