Is it permissible for a husband to threaten his wife with divorce and not defend her against his family, even though the wife accepted him despite the presence of a hereditary disease in his family?

The wife is advised to be patient and to treat her husband well, reminding him of the Prophet’s (peace be upon him) وصية (injunction/bequest) regarding women: "Treat women well," and his saying: "The best among you is the best to his family." She should also overlook minor faults. If advice is ineffective and the matter escalates to harm, she then has the right to seek the removal of harm or divorce.