What is the ruling on shunning a father who abuses his daughter with severe beatings and insults her? Is he permitted to strike his daughter on her face? Is diabetes considered a justification for his actions? And does a husband's divorce take effect if he swore to divorce his wife due to the children's stubbornness?

It is not permissible for a father to oppress his children or beat them severely, but this action of his does not negate his right to dutifulness. Feeling hatred towards him unintentionally is not blameworthy, but you should try to remove it. You erred by confronting him during his anger, and you must mend the relationship by being kind to him. If you wish to advise him, wait until he calms down. The father's action of striking your face and insulting you is impermissible, and he is sinful for it unless he was unconscious. As for the issue of your mother's divorce, a ruling cannot be given without knowing the form of the divorce and whether the condition upon which it was suspended occurred or not. If the father swore by divorce that you would go with him and you did not go, then the divorce occurs according to the majority of scholars, and some say that a کفارة يمين (expiation for an oath) suffices if he intended to urge and emphasize. If the divorce occurred, he can take her back before her waiting period (iddah) ends, unless it was the third divorce.