How can one deal with a father who constantly insults the family and children and refuses advice, accusing his children of disobedience when they try to advise him, knowing that this behavior negatively affects the children's health and psyche?

Fighting with one's father and being disobedient to him is a grave sin. No matter how much a father wrongs or oppresses, it is not permissible to return evil with evil. Rather, one must show kindness and benevolence towards him. Advice should be given gently and kindly. If he responds, then that is good. Otherwise, you should leave it; because if reminding him does not benefit—by increasing evil or decreasing good—then it is not commanded. Patience, avoiding what provokes the father, praying for his rectification, and attempting to have some respected individuals advise him are among the greatest acts of piety towards him. If you find a dislike for him in your heart, there is no sin upon you for that, because a person has no choice in matters of the heart. Nevertheless, strive to obey him in what is good.