I think the thing that Hasselback said that so wounded Rosie, after Rosie had complained that Elizabeth had not defended her, was "You are an adult. Defend your own insinuations."
Rosie's mother died when she was a child. Apparently her inner "wounded child" is still looking for a mother to defend her in the scary world, where there are frightening adult things like men, sex and war. This exchange was deeply primal. Elizabeth called Rosie on her weakest point.
BINGO!!