Is a wife held accountable for praying for her husband to fall ill in retaliation for his harming her and ridiculing her illness, and how can she retract this prayer, and what is the ruling on his ridiculing her illness?

It is permissible for a wife to supplicate against her oppressive husband if he harms her unjustly. However, it is better to refrain from doing so. It is preferable for the wife to seek forgiveness for her husband, apologize to him, and pray for his pardon and well-being, in order to restore the good relationship between them. This should be done by seeking Allah's help and through gentle and kind understanding.