The title of the story "The Jilting of Granny Weatherall'' refers to the main character's most conflicting moment in her life, and it is the precise life event that Granny Weatherall has continuously tried to battle out of her mind. It is the one situation that changes her life forever. It affects her to the point that it follows her to her deathbed as if it were ghost that is consistently taunting her memory, not giving up the taunting until she addresses it and lets it go.
By choosing this title the author confronts the main character by openly telling the reader what Granny's real problem is: That she has lived a life of self deceit in a constant quest to prove to herself that she has been able to overcome that one horrid instance.
We know that, after the jilting, Granny's life becomes a chain of decisions that are meant to show to the world that she is OK. Yet, at the very end, we see clearly that, instead of brushing off her jilting and moving on with her life, Granny actually carried that moment in her subconscious until the moment of her death.
Hence, the author wants to liberate the main character by telling her secret. This is a way for us to clearly understand why she is where she is at the moment of her death in terms of her mental and spiritual state of mind.