Terminal decline of satisfaction in romantic relationships: Evidence from four longitudinal studies.

In this preregistered research, we tested whether there is a systematic, terminal decline in relationship satisfaction when people approach the end of their romantic relationship. Data came from four longitudinal studies with national samples. In the analyses, we used (piecewise) multilevel models with propensity score-matched event and control groups. Across studies, sample sizes ranged from 987 to 3,373 for event groups and from 1,351 to 4,717 for control groups. Relationship satisfaction systematically declined as a function of time-to-separation. The decline prior to separation was divided into a preterminal phase, characterized by a smaller decline, and a terminal phase, characterized by a sharp decline. Across studies, the onset of the terminal phase was estimated at 0.58-2.30 years prior to separation. For comparison purposes, we also examined relationship satisfaction as a function of time-since-beginning, showing that time-to-separation was a much better predictor of change than time-since-beginning. Moreover, for comparison purposes, we examined change in life satisfaction, showing that terminal decline was less visible in life satisfaction than in relationship satisfaction. Moderator analyses indicated that age at separation and marital status explained variance in the effect sizes. Moreover, individuals who were the recipients of the separation (in contrast to individuals who initiated the separation) entered the terminal phase later but then decreased more strongly. The findings support that ending relationships show a typical pattern of preterminal and terminal decline, which may have important implications for the timing of interventions aimed at improving relationships and preventing separation. (PsycInfo Database Record (c) 2025 APA, all rights reserved).