<p>There is a growing interest in non-monogamy worldwide. At the same time, there is still little scientific research on the topic in Poland, which culture is sill strongly based on mononormativity and catholic culture. The article is based on exploratory qualitative study (in-depth interviews)of non-monogamous people in Poland. The aim of this article is to present the results of an analysis of consensually non-monogamous adults understanding of love, relationship and infidelity. The results indicate that non-mogamous participants have very different understandings of these concepts, but there is a distinct rejection of traditional patterns of romantic love, and an avoidance of defining or naming a relationship to avoid the social expectations attached to these labels. There are also strong tendencies to individualise and autonomise norms, rules and boundaries. This, however, leads to ambiguity and difficulty in defining, and mixing different elements together. The research also raises questions about wider social change in the area of romantic relationships and the semantics of love in the post-modern era.</p>