Teacher wellbeing is a growing international concern. Despite teachers' experiences being deleteriously impacted by education policies and organisational conditions, dominant discourses of wellbeing focus on strategies that enhance individual self-management of wellbeing. This paper critically examines teacher wellbeing and the counter-discourses of wellbeing mobilised by teachers on an online platform, Reddit. Contributors criticise the wellbeing approaches taken in their schools and education systems. They react to the erasure of how work conditions impact their wellbeing. These forums speak back to the assumption that teachers are deficient and that teachers must be positive in self-managing their wellbeing. We coin the term 'cruel wellbeing' to critique wellbeing programs that neglect teachers' challenging work conditions. We question the practices of training teachers to assume responsibility for their wellbeing using strategies of positivity. We suggest that social media is an important political tool for creating and circulating counter-discourses of teachers' work.