"Shiloh" is the title story from Bobbie Ann Mason's 1982 anthology Shiloh and Other Stories.
The disaffected couple in "Shiloh," Norma Jean and Leroy, visit the Civil War memorial at Shiloh in an attempt to rekindle their relationship. However, the attempt fails because of the rift brought between them by Leroy's injury, Norma Jean's mother's interference, and their mutual failure to sit down and talk things out.
Leroy is trying to comprehend that his marriage is breaking up, but for some reason he is wondering about white slabs in a graveyard.
"Everything was fine till Mama caught me smoking," says Norma Jean, standing up. "That set something off."
"What are you talking about?"
"She won't leave me alone -- you won't leave me alone." Norma Jean seems to be crying, but is looking away from him. "I feel eighteen again. I can't face that all over again." She starts walking away. "Not, it wasn't fine. I don't know what I'm saying. Forget it."
(Mason, "Shiloh," Google Books)
Leroy's mind is foggy because of his marijuana use, and Norma Jean feels trapped by his lack of work and her mother. She walks away and waves to Leroy, and he can't figure out if she's waving goodbye or stretching. Leroy also can't fully comprehend that Norma Jean is unhappy, since he is fine with staying home, smoking weed, and generally doing nothing; she doesn't want him around the house all the time, and feels like her freedom is being taken away.