This article examines the seminal contributions of Britain's marriage counseling and therapy services toward cultivating a new emotional purpose for marriage in the decades following World War II. It presents two related narrative threads. First, it argues that psychologically oriented relationship services attracted government support because they supported the postwar ideal of a classless democratic society. Pioneering practitioners promoted a universalized view of citizens’ emotional relationships—rather than their socio-economic circumstances—as the determining fact of their lives. Second, it argues that these services provided a compelling language and set of concepts for articulating transforming understandings and expectations of marriage in the decades after 1945. To this end, the article reveals how the language and concepts of marriage therapists were mobilized by divorce reformers in the 1960s, and helped replace the offense model for divorce petitions with a less punitive psychological model of relationship “breakdown” in 1969. Britain's postwar marriage welfare services endowed stable harmonious families with crucial social and political importance as the bedrock for postwar social reconstruction and the most fitting environment for children and adults alike to develop into fully mature and self-realized democratic citizens.