Sharyl E Toscano from the University of Vermont interviewed 22 girls aged 15-18 from two Massachusetts high schools. She asked them about their own dating experiences and those of their friends, the influences on those relationships and any experiences of abuse.
From these interviews Toscano identified seven stages in the dating cycle. The couple-to-be typically first meet when their circles of friends interact. They get to know each other better outside the group, but only in a very limited capacity (internet, phone). Next, they start to go out together with other couples (i.e. a "group date") before dating independently of their friendship groups. At this point they re-enter the friendship circle as a recognised couple, maintaining their independent relationship as well as their relationships with in the circle. After a break-up the two have to re-join the circle as independent members once again.
It was found that the circle sets the social rules, norms and values for the dating relationship; friends act as a safety net against anyone not sharing their "terms of engagement." The risk of abuse - an intention to cause verbal, emotional or physical hurt - is greatest at times of stress and when the dating relationship remains outside of the girl's friendship circle (for example when the friends reject the partner).
Toscano also argues that without the circle's support, teenage girls are more uncertain about possible abuse. They see physical abuse as play fighting, control as protection, and sexual pressure (even rape) as normal sexual tension. Girls tend to tolerate abuse more when they fear losing a relationship, when they have lost their virginity or when the relationship involves sexual activity.
When girls are uncertain about possible abuse they look to their friends for confirmation (especially when physical abuse has left visible marks). Friendship groups often act to protect the girl and, in the most severe cases, approach a trusted adult (often a parent) for help. But a girl who has been isolated from her friends is less likely to receive help this way; she may cover up any abuse because she feels shame.
Toscano asserts that the relationships of teenage girls with their peers could be a key indicator for healthcare providers and parents of the risk of abuse (including sexual pressure) in a teenage dating relationship. The maintenance of a strong friendship circle reduces a girl's uncertainty about, and consequently protects her from, abuse.