Using a sample of 532 nonmarried adults over age 65 residing in the District of Columbia and two adjoining Maryland counties, this study examines "single strain"--the strain of not being married or not living with a partner in late-life. First, I consider how social and economic statuses affect exposure of nonmarried elders to single strain. Second, I study how sociodemographic characteristics and psychosocial resources moderate the effect of single strain on mental health. Results of multiple OLS regression analyses indicate that while social statuses influence elders' exposure to single strain, the differential emotional responsiveness of nonmarried older adults to single strain is largely unaffected by their sociodemographic characteristics. In contrast, mastery and self-esteem are powerful moderating resources: Nonmarried elders with high mastery and self-esteem are less adversely affected by single strain than those with lower levels of intrapsychic resources.