What does Catherine talk to Aunt Ethelfritha about when she runs away in September?

When Catherine runs away from Shaggy Beard's men, she goes to her Aunt Ethelfritha. They talk about running away together to Ireland or London, but her aunt is obviously insane. Catherine begins to think about the Jewish woman she met on the road, and realizes that she carries her family with her and no matter where she goes, she is still herself.