Final answer:
Mr. Kapasi is offended by Mrs. Das's confession in 'The Interpreter of Maladies' because he had hoped for a meaningful connection, but she treated her infidelity trivially, shattering his idealized perception of her.
Step-by-step explanation:
In The Interpreter of Maladies, Mr. Kapasi is offended by Mrs. Das's confession because he sees her not just as a casual tourist but as someone capable of understanding the depth of his life and emotions. As an interpreter of maladies, he was hoping to form a meaningful connection with Mrs. Das through their exchange of stories and was perhaps searching for an escape or solace from his own discontented life.
When Mrs. Das first confides in him, revealing her secret purely as a means to ease her guilt and not as a step towards mutual understanding, it shatters Mr. Kapasi's idealized vision of her. He is not just offended by the triviality with which she treats her infidelity but also by the realization that she does not see him in the light of a potential emotional ally. When she first confesses, he questions the nature of her affliction, initially assuming it to be a physical malady he might interpret.