The substantial number of young people in romantic relationships that involve intimate partner violence, a situation deleterious to physical and mental health, has resulted in increased attention to understanding the links between risk factors and course of violence. The current study examined couples’ interpersonal stress related to not liking partners’ friends and not getting along with parents as contextual factors associated with couples’ psychological partner violence and determined whether and when couples’ friend and parent stress increased the likelihood of couples’ psychological partner violence. A linear latent growth curve modeling approach was used with multiwave measures of psychological partner violence, friend stress, parent stress, and relationship satisfaction obtained from 196 men at risk for delinquency and their women partners over a 12-year period. At the initial assessment, on average, the men were age 21.5 years and the women were age 21 years. Findings indicated that couples experiencing high levels of friend and parent stress were more likely to engage in high levels of psychological partner violence and that increases in couples’ friend stress predicted increases in couples’ partner violence over time, even when accounting for the couples’ relationship satisfaction, marital status, children in the home, and financial strain. Interactive effects were at play when the couples were in their early 20s, with couples being most at risk for increases in psychological partner violence if they experienced both high friend stress and low relationship satisfaction. Couples’ friend stress had the greatest effect on psychological partner violence when the couples were in their early to mid 20s when levels of friend stress were high. As the couples reached their 30s, low relationship satisfaction became the leading predictor of couples’ psychological partner violence.