The neural basis of dilemmas involving decisions with profound affective impact, such as in romantic life, remains to be understood. The "Battle of the Sexes" is a paradigm from Game Theory that can be used to experimentally address such dilemmas. A form of in-group love, tribal love in football fans, provides the opportunity to study strong affective dilemmas when tribal and romantic love compete for hedonic decision-making. Here, we used for the first time a "Battle of the Sexes" dilemma using fMRI. We investigated, in 44 male football fans, the neural correlates of cooperative behaviour under conflicting choices in the context of romantic versus tribal love. We identified a critical functional segregation of prefrontal regions in affective decision-making. The orbitofrontal cortex signalled emotional appraisal of the dilemma. The medial anterolateral and the ventromedial prefrontal cortices reflected reciprocal cooperation instead of selfish engagement in football-related activities. The lateral portion of anterolateral prefrontal cortex was recruited during ultimate deliberation. In sum, emotional appraisal and rational choice reflected a contiguous functional parcellation in anterolateral prefrontal cortex: appraisal (medial) vs. choice (lateral region).