Is it permissible to refrain from marriage due to thinness, fearing the husband's injustice or falling into divorce?

You must abandon obsessive thoughts and strive to gain weight through permissible means. Fear of divorce is one of Satan's ploys, for what was destined to befall a person could not have missed him, and what was destined to miss him could not have befallen him. There is no injustice in a man marrying a woman whom he has approved after seeing her, and who has not concealed from him any hidden flaw or deceived him with qualities she does not possess. If a righteous husband is found and he agrees, do not hesitate to accept him, and ask Allah for success by saying: "Our Lord, grant us from our wives and our offspring comfort to our eyes."