Abstract Introduction There has been an upsurge of research articles in the last two decades about sexual addiction (SA) and compulsive sexual behaviour (CSB). In the literature, SA/CSB is mainly presented as comparable to other behavioural addictions and similarly involves a problematic consumption model: loss of control, psychosocial impairments, and risky sexual activities. Despite this recent rise in research interest in this area, only a small number of studies have focused on the partners’ lived experiences and well-being. Methods This qualitative descriptive phenomenological investigation aimed to examine female partners’ lived experiences and well-being following the discovery or disclosure of their male partners’ SA/CSB. Individual in-depth semi-structured interviews were conducted (2020–2022) with primary participants (female partners; n = 12) and supplementary participants (counsellors; n = 15). Results The analysis reveals that this group has encountered several detrimental consequences of CSB-associated betrayal trauma (BT), including but not limited to suicidal thoughts and self-harm, compulsive self-comparisons with other women, physical and behavioural difficulties, and diminished self-esteem. Conclusions This empirical research is the first study in Australia to examine the voices and experiences of female partners upon learning of their mates’ CSBs. The findings contribute to the field of SA/CSB and enhance understanding of the multifarious consequences for the emotional, physical, sexual, spiritual and/or relational well-being of intimate female partners and their general outlook on life. Policy Implications Based on the results, there are strong indications with implications for policy that this population requires validation and multifaceted support systems to better navigate the challenging, complex, and stressful processes of discovery/disclosure and subsequent recovery.