Underground Time, by Delphine de Vigan.
Translated from the French and set in Paris, this novel takes place on 20 May, the exact date a soothsaying fortune-teller told Mathilde there would come a (much-needed) change in her life. Mathilde feels herself disintegrating. Her boss has turned on her and has been making her job and her life unendurable for months and months. Physician…