In A Streetcar Named Desire, what does Blanche tell Stanley about illusion and truth and what truth does she reveal?

In Scene 2, Blanche tells Stanley that "a woman's charm is fifty percent illusion."  She explains that is the reason that she fibs a lot, to create an illusion that is attractive.  However, she does claim that when something is important, a woman - herself included - will always resort to the truth.  In other words, a woman knows between right and wrong.  Blanche explains that she knows she fibs a lot, because “after all, a woman’s charm is fifty percent illusion,” but when something is important she always tells the truth.  The truth that Blanche shares is what she has already told - that the estate was lost, not sold.  She shares with him the papers, and explains the mismanagement of funds and slow decline of the estate.