Difficulties in identifying and describing feelings, social constraints, affect, and functional well-being among Chinese breast cancer patients: A mediation model

•Functional well-being (FWB) among Chinese breast cancer survivors' was understudied.•We examined how barriers of emotional processing and expression associated with FWB.•Negative affect mediated between difficulty in describing emotions and FWB.•Positive affect mediated between difficulty in identifying emotions and FWB.•Both positive and negative affects mediated between social constraints and FWB.