What is the ruling on obeying the mother when she screams at the father and supports him in a dispute, knowing that she is ill and verbally and physically abuses him, and he supplicates against her?

One must honor and show kindness to one's parents, avoiding mistreatment and demonstrating humility, as Allah Almighty says: "And your Lord has decreed that you shall not worship except Him, and to parents, good treatment. Whether one or both of them reach old age [while] with you, say not to them [even] 'uff,' and do not repel them but speak to them a noble word. And lower to them the wing of humility out of mercy and say, 'My Lord, have mercy upon them as they nurtured me when I was small.'" It is not permissible to obey the mother in disrespecting the father or in any forbidden act, and doing so is not disobedience to her. Imam An-Nawawi mentioned that forbidden disobedience is every act by which a parent is significantly harmed, and which is not among the obligatory actions.