Individuals frequently make choices for others. However, little work has examined the emotional quality of doing so or explored how relationship factors affect such choices. In three experiments and one longitudinal study, we explore how relationship interdependence (i.e., mutual involvement with and reliance on one’s partner) influences individuals’ emotions when choosing for their romantic partner. Our studies show no effects of relationship interdependence on positive emotion but reveal that individuals high (vs. low) in relationship interdependence feel more negative emotion when choosing (vs. not choosing) for their partner. Via mediation and moderation, we show that this negative emotion arises because individuals higher in relationship interdependence view choosing for their partner as having more potential negative consequences. Our data suggest that the negative emotion experienced by those high in relationship interdependence can negatively impact relationship quality, which may have implications for individuals’ mental and physical health and their overall well-being.