Antonyms for the phrase "became husband and wife" could include the words "split up," "separated," "divorced," or "annulled." These words suggest a dissolution of a marriage, rather than a joining together. Other antonyms could include "unmarried," "single," or "unattached," which indicate that the two people involved have not yet entered into a committed partnership. Still, other possibilities could include "estranged," "alienated," or "disconnected," which suggest a breakdown in the relationship between the two individuals. Whatever the antonym used, it stands in direct contrast to the idea of two people coming together to form a lifelong commitment as husband and wife.