What is the Sharia ruling regarding a wife who refuses to sleep with her husband for four years due to fear of pregnancy, and suggests external masturbation to him, which has caused him psychological distress and addiction to tranquilizers; and is divorce the solution in this case?

A wife's refusal to share her husband's bed without a valid excuse is an act of nushuz (disobedience), which warrants condemnation and the forfeiture of her rights. Methods for addressing nushuz are mentioned in Fatwa No. 44245. If these methods have been exhausted and the wife does not abandon her nushuz, it is then recommended to divorce her, based on the Prophet's (peace and blessings be upon him) saying: "There are three whose supplications are not answered: ...and a man who had a ill-tempered wife but did not divorce her." It is advised to be deliberate and weigh the benefits of divorce against its harms, especially concerning the daughters.