<p>Divorce and separation are some of the most traumatic life events experienced by women, posing serious consequences for wellbeing. The impact of later-life relationship dissolution has been neglected in the literature. This study aimed to compare decades-long life satisfaction trajectories of Australian middle-aged women who did, and did not, experience relationship dissolution, and to examine why some women adjust better than others. Prospective longitudinal data came from nine waves of the Australian Longitudinal Study on Women’s Health. Women who divorced or separated during the study (<i>n</i> = 1462) were propensity-score matched to women who remained married or partnered (<i>n</i> = 2587). Results from Bayesian piecewise latent growth curve modelling indicate stable life satisfaction before relationship dissolution, a sudden decline in the years surrounding the event, and long-term increases thereafter. Matched controls showed stability and slight increases in life satisfaction across the observation period, which suggests that at least some change in life satisfaction experienced by divorced and separated women is associated with relationship dissolution. Social support, perceived control, and subjective income were significant positive moderators of women’s adjustment to relationship dissolution. Implications regarding wellbeing interventions for middle-aged women are discussed.</p>