This study was designed to further understand passionate friendships in a sample of heterosexual and lesbian, bisexual, and questioning (LBQ) women. Previous research has established that LBQ women engage in same-sex passionate friendships (unusually intense friendships that are similar to romantic relationships but devoid of sexual intimacy), but no systematic classification system has been established to identify these relationships in a general sample of women. A new quantitative measure, the Passionate Friendship Survey, was developed to measure passionate friendship experiences in women across adolescence and young adulthood. Qualitative interviews were also conducted to understand the subjective experience of passionate friendships in heterosexual and LBQ women.

Passionate friendships are present in both heterosexual and LBQ women during adolescence and young adulthood, but are developmentally more likely to occur during adolescence and are correlated to more positive outcomes during adolescence compared to young adulthood. Passionate friendships also appear to serve different functions related to exploration and integration of sexual orientation for LBQ compared to heterosexual women. Characteristics, correlates, and functions of passionate friendship are presented as well as recommendations for future research in this area.