<p><strong>Over the past two decades, anti-stigma campaigns have successfully reduced public stigma associated with mental illness and increased awareness of these conditions. However, these efforts may have also contributed to the normalisation and trivialisation of mental illness, creating an additional barrier for young adults seeking help. Trivialisation where mental illness is minimised or downplayed—remains an underdeveloped area of research, particularly regarding its impact on help-seeking and disclosure among young adults. This thesis explored how the trivialisation of mental illness impacted young women’s experiences of help-seeking, diagnosis, and disclosure. A qualitative, social constructionist framework guided this research. Seven young women (aged 19–25) living in Aotearoa participated in semi-structured interviews conducted online or in person. Data was analysed using Reflexive Thematic Analysis, resulting in the creation of four themes; (i) The Nature of Trivialisation; (ii) Anger, Hurt and Acceptance – Immediate Reactions to Trivialisation; (iii) “It sticks with you” – The Lasting Impact of Trivialisation; and (iv) Improving Mental Health Support: Recommendations and Advice. Findings demonstrate the immediate and long-term impacts of trivialisation on young women’s perceptions of their mental illness, their willingness to disclose, and how they sought treatment and support. Many participants reported self-trivialising their mental illness, where they internalised the trivialising attitudes of others and minimised their own experiences. Additionally, trivialisation acted as a barrier to professional help-seeking, leading to self doubt, hopelessness, and a reluctance to seek help. This research has important implications for health professionals (particularly front-line mental health workers), mental health campaigners, and researchers. Trivialisation is a significant barrier that young adults with mental illness must navigate when seeking help and disclosing their condition. Addressing this requires greater awareness of trivialisation and its impacts, alongside changes in public attitudes and targeted mental health interventions.</strong></p>