What is the ruling on shunning one's mother and subjecting her to hurtful words because she committed zina previously to secure a livelihood for her children, with the husband's knowledge and consent?

The mother's right over her children is great, and it is not nullified by her corruption or disobedience. Allah has commanded to accompany the polytheist parent with kindness. Children must honor their mother and not abuse her. However, if she does not repent from her indecency, they must forbid her from it and prevent her by all means without being harsh. It is not permissible to boycott her unless boycotting is the only way to prevent her from indecency, while continuing to maintain ties with her through financial support and the like. Her husband must also be advised to repent, and it should be clarified to him that he is a "dayyuth" (one who tolerates indecency among his womenfolk) if he condones her committing indecency.