When we speak about relationships, as in "in my current relationship," we often mean our current romantic/sexual partner. This points to the the central position this kind of relationship holds in our societys understanding of relationships and the priority it is given. Having moved past tribe, extended family, and nuclear family, mainstream western society is geared towards couples, though just barely - singles are approaching the top position. This is no accident but a direct result of industrial capitalism. The smaller the unit of human habitation the larger the market.