Being a member of a rejected group negatively affects well-being but can also increase group identification, which can have positive effects on well-being. However, this rejection-identification model has never been investigated among the highly stigmatized group of ex-prisoners. Furthermore, the potential buffering role of multiple group memberships has never been investigated within the rejection-identification model. We conduct a novel investigation of a combined rejection-identification and social cure model of group-based rejection among ex-prisoners. A survey of 199 ex-prisoners found that experiencing group-based rejection was associated with poorer well-being and increased ex-prisoner identification. However, identification as an ex-prisoner magnified, rather than buffered, the relationship between rejection and reduced well-being. Furthermore, the negative relationship between rejection and well-being was particularly pronounced among ex-prisoners with a higher number of group memberships. Ex-prisoners with a greater number of group memberships experienced greater levels of rejection, suggesting group memberships increase their exposure to rejection. We therefore provide evidence of a boundary condition for the social cure properties of groups. Among members of strongly rejected social groups, multiple group memberships can be a social curse rather than social cure.