late purple aster: a variety of aster
aster: any of various chiefly fall-blooming herbs of the genus Aster with showy daisylike flowers
survivor guilt: a deep feeling of guilt often experienced by those who have survived some catastrophe that took the lives of many others; derives in part from a feeling that they did not do enough to save the others who perished and in part from feelings of being unworthy relative to those who died