What is the jurisprudential ruling concerning a wife who confessed to adultery with a Christian man, knowing that she is a muḥṣanah (chaste, married woman) and wears a niqab (face veil), and knowing that her husband's absence from her for more than four months might have been a reason for this?

It is not permissible for a husband to be absent from his wife for more than six months unless she consents. She has the right to seek a divorce if he does not comply. It was incumbent upon the wife to be patient and not to fall into adultery; she could have sought a divorce. She must perform sincere repentance. It is not permissible for the husband to accuse her of adultery without evidence or to threaten her into confessing, and her mistake was in confessing. If she repents, then keep her and live with her honorably, and do not pay attention to whispers [of doubt]. Be keen on preserving her chastity. Do not elaborate on describing the betrayal, as that might be from the whispers of Satan.