The importance we attribute to our friendships changes throughout our lives. Up through the fourth grade, most children look to their family as their sole source of emotional support (Furman & Simon, 1998). When children suffer a disappointment at school, have frightening dreams, or just want to share the events of the day, they will turn to parents or siblings. But during adolescence, children slowly transfer their emotional attachment from their family to friends (Welch & Houser, 2010). For example, by the seventh grade, young people rely just as much on same-sex friends as they do on family for support. By tenth grade, same-sex friends are the principal providers of emotional support. This trend continues into early adulthood: for college students, friends are the primary relationship for fulfilling relational needs (McEwan et al., 2008).

By middle adulthood, many people form long-term romantic commitments and start families of their own. Consequently, their romantic partners and children become the primary providers of companionship, affection, and support. The importance of friendships begins to wane (Carbery & Buhrmester, 1998). This is especially the case for married men, who before marriage tend to spend most of their time with male friends (Cohen, 1992). Late in life, however, the pattern shifts back once more, as spouses and siblings pass on and children form their own families. For the elderly, friendships are the most important relationships for providing social support and intimacy (Patterson, 2007).