Lebanon’s intersecting economic and political crises exacerbate complex public health issues among both host and refugee populations. This mixed-methods study by a Lebanese service provider, in partnership with an international research institute, seeks to better understand how experiences of gender-based violence (GBV) and mental health intersect in the lives of Syrian and Lebanese women, and how to better meet these needs. It employs a randomized cross-sectional survey of 969 Abaad service users and focus groups with community members and service providers. There were significant associations between GBV and ill mental health; notably, respondents reporting transactional sex had 4 times the likelihood of severe distress (aOR 4.2; 95% CI 1.2–14.8; p ≤ 0.05). Focus groups emphasized less-visible forms of violence, such as emotional violence, and the importance of environmental factors in one’s ability to cope, noting “it always came back to the economy”. Recommendations include providing a more holistic and coordinated approach between GBV, mental health, livelihood, and basic assistance sectors; and sensitive, accessible, and higher-quality mental health services informed by GBV response actors’ experience putting in place survivor-centered programming and made available to both host and refugee community members.