Abstract: This participatory research project explores lessons learned from conducting patient and public involvement (PPI) with a marginalized group of women experiencing homelessness, comorbidities, and deep mistrust in institutions, care systems, and themselves. Often excluded from traditional structures of influence, these women face overlapping cognitive, psychological, physical, and social challenges, making their participation in research both vital and complex. Based on 15 sessions with a co-creative working group, this work underscores the importance of flexibility, relational ethics, and environment when involving individuals whose lives are far removed from mainstream society. Anchored in a person-centred approach and influenced by the relational philosophies of Martin Buber and Carl Rogers, our work emphasizes the power of genuine dialogue and the need to meet people as whole, complex human beings—seeing participants not merely through the lens of problems or diagnoses. The process illuminated how consistent structure, shared rutines (e.g., communal meals), and respect for each woman’s unique rhythm of engagement fostered a sense of safety and belonging. Over time, participation enabled the women to renegotiate their self-image and sense of capacity. Through relational experiences and creative expression, new personal narratives emerged—allowing for complexity, contradiction, growth and agency. Key lessons include the need for non-linear, creative methods to support diverse forms of expression; the importance of acknowledging power imbalances; and the ethical balance between personal transformation and the research agenda. For PPI to meaningfully contribute to person-centred care, it must resist becoming standardized or uniform. Instead, it must allow for multiplicity and be grounded in lived experience—especially the voices of those furthest from care, power, and trust.