Is it considered disobedience to parents if I am unable to deal with my father due to his bad behavior and repeated insults? And does my religion demand that I interact with him and offer him help despite the psychological harm he causes me?

There is no harm in your distancing yourself from your father if it is not due to severing ties with him and he is not harmed by it, especially if you fear that he might cause you harm. By doing so, you are not considered disobedient to him. If he requests your help, you are obligated to obey him as long as no harm befalls you, for Sheikh al-Islam Ibn Taymiyyah said: "A person is obligated to obey his parents in matters that do not involve disobedience, even if they are disobedient [to Allah]." And praying to Allah to guide your father is one of the greatest acts of righteousness towards him.