As Granny dies, she seems to become a small “point of light” that leaves her earthly body. “The blue light from Cornelia’s lampshade drew into a tiny point in the center of her brain […] Granny lay curled down within herself, amazed and watchful, staring at the point of light that was herself; her body was now only a deeper mass of shadow in an endless darkness and this darkness would curl around the light and swallow it up.” At the very end of the story, she then “blew out the light.”
On one level, this light seems to represent Granny’s life. As she blows it out, she chooses to end her own life, on her own terms. However, the light could also represent Granny’s sense of hope. She blows it out after God fails to give her a sign of reassurance in the face of her death, perhaps because she loses her faith in God as a result of this. What is interesting is that Granny herself blows out the light, and it is not simply put out. By blowing out the light, she chooses to assert her own agency in the face of God failing her, and demonstrates her strong will in doing so. She chooses to put her faith in herself, rather than in God. Just as she did not lose her determination and agency after her first jilting by her fiancé George, she doesn’t stop asserting herself even in the face of death and spiritual abandonment.