What assumption about the woman's life does the speaker make in "when you are old"?

It is that "she has never known his love and so should be sad". (And hid his face amid a crowd of stars).

When you are Old was authored by William Butler Yeats who was born in 1865. He was an Irish writer and one of the premier figures of twentieth century writing, a mainstay of both the Irish and English literary foundations. In his later years filled in as an Irish Senator for two terms.

what is the question you are trying to ask?

answer; presidential election years;