Abstract
<p>Strong social connections fundamentally shape human well-being and influence how individuals interpret their world. While previous research highlights the importance of friendships for well-being, the role of mental representations of friendships remains less explored. Since friendships involve both cross-situational variability and multidimensional features, capturing their complexity requires approaches that move beyond single indicators of relationship quality or quantity. This study examined whether higher well-being is associated with greater similarity in mental representations of friendships across contexts, consistent with the Anna Karenina Principle. We developed a two-level friendship rating task to assess mental representations of friendships across different dimensions and contexts. Using rating task data from 1,190 participants, we applied intersubject correlation analysis to quantify similarity in mental representations of friendships. We then identified latent dimensions of friendship representations and tested which dimensions were significantly associated with well-being. We found that greater similarity in mental representations of friendships was associated with higher well-being. We then identified three friendship dimensions, including socio-emotional, instrumental, and collectivism, with only the socio-emotional dimension strongly linked to well-being. Our findings suggest that well-being is associated not only with friendships themselves, but also with how individuals mentally represent the socio-emotional aspect of friendships. Shared socio-emotional factors may be an important psychosocial factor linking social connectedness and mental health.</p>