In Flannery O'Connor's short story "Everything That Rises Must Converge," what is the symbolic significance of the hat?

The short
story "" bytells of a man named Julian who lives with his mother in the recently
desegregated American Deep South. She is attending a weight-reducing class at the Y, and Julian
accompanies her because she does not like to take the bus alone. On the way, Julian's mother
exhibits her blatant racism through her conversation and expressions.

At the start of the story, as they are preparing to leave, Julian's mother
puts on a garish hat that she has recently bought. O'Connor shares Julian's opinion of
it:

It was a hideous hat. A purple
velvet flap came down on one side of it and stood up on the other; the rest of it was green and
looked like a cushion with the stuffing out. He decided it was less comical than jaunty and
pathetic.

Julian's mother at first
cannot decide whether to wear the hat or not. She comes to the conclusion that "you only
live once." To her, the hat imparts an illusion of grandeur and of aristocracy and
reminds...