We examine the psychosocial impact of marital status change, and the spontaneously emerging theme of identity. In-depth interviews were conducted with 82 cohabiting, married, widowed, and divorced British adults, focusing on changes in daily routine, social relationships, and social support. We draw attention to findings of interviews with men and women who entered a married (n = 30) or cohabiting (n = 8) relationship for the first time. The interviews provide an insight into the complex process of identity change in marriage and cohabitation. Participants described an identity shift from "I" to "we" which was associated with social and personal changes in how they understood themselves. Marriage and cohabitation were viewed as positive transitions facilitating personal growth. However, importantly, marriage, in particular, was also associated with a process of depersonalization which posed a challenge to private identity. We conclude with a discussion of the ways in which participants managed this identity conflict.