A long-term study involving 1925 couples demonstrates that healthy partnerships may positively alter personality traits. Researchers found that being in a good relationship can mitigate narcissism and other undesirable personality characteristics, often referred to as “dark traits.” The study tracked couples over time, observing changes in individual behaviors and attitudes within the context of the relationship. This suggests that the dynamics of a supportive partnership can encourage personal growth and self-awareness, lessening narcissistic tendencies. These findings challenge the notion that personality is fixed, highlighting the impact of close relationships. The research indicates that positive relationship experiences can lead to beneficial changes in personality over the long term, offering a form of “therapy” through partnership itself.