This novel seems perfectly normal on the surface, but a considerate reader will notice that the observations Welty draws about human nature are actually quite macabre, and perhaps even disturbing. For the best example of this, consider Fay, who admits that in a sick, twisted way, she did want her husband to just die already. Then, when he dies, she feels a kind of cosmic horror around her experience of guilt. She has to wonder what the nature of life really is.
In other words, she has to wonder about the true nature of death. In her life, she has always just been motivated by her desires. In private conversation, she observes that he never really caught on, but she was always just using him because he gave her so many chances to fulfill her desires. When she started to want more than he was willing to give her in her allowance, she began stealing from him. Of course, there was no intimacy, so she often desired sexual company, and—not giving it to her own husband—she tells us that she found affairs.
But now, he is dead. So the novel asks the question. Was this the perfect crime? Will she get away with it, so to speak? Notice that later when Laurel begins to talk about herself, Fay is disinterested and rude. Why? Because she has not figured out her ego-centric issues, because she is just beginning to understand the stakes of human responsibility. Ultimately, that is the horror of Welty's Optimist: the sublime possibility that perhaps we will all be judged in the afterlife. After all, Welty is well-known for combining Southern religious motifs with horror.
