What should a Muslim do if he supplicates against himself—despite the impermissibility of that—and Allah answers his supplication, and he wishes to avert what he cannot bear?

A supplication that is not permissible in Sharia might be answered if it coincides with a time of response. Therefore, the Prophet (peace and blessings be upon him) forbade supplicating against oneself, one's children, and one's wealth, fearing that it might coincide with a time of response. For treatment, it is recommended to turn to Allah and supplicate frequently and persistently, for supplication is one of the most important means by which Allah wards off affliction, and "nothing repels divine decree except supplication," just as supplication "benefits against what has descended and what has not descended." Supplicate to Allah during times of response with His Greatest Name, and with the supplication of Yunus: "There is no deity except You; exalted are You. Indeed, I have been of the wrongdoers."