Coriolanus’s jealousy in this moment emerges for the same reasons he got jealous after Lucy Gray sang during her interview. It’s clear that she has a life here, a following, and is attractive to everyone—which, combined, dilutes Coriolanus’s power over her. Put another way, she obviously doesn’t need him to protect her here; she can fend for herself. And Coriolanus justifies their relationship to himself by casting himself as her protector, as it gives him power within the relationship.