What is the reason for a husband's change in behavior towards his wife when they are with his family, and his inability to make decisions without his father's approval? Is this related to magic or fear of his family?

A man's obedience to his father is obligatory in what is good, not in disobedience. A husband is not to obey his father in mistreating his wife. The wife should be patient, and if she believes he has been afflicted by magic, she should perform the ruqyah (Islamic exorcism). The husband's consulting his father in all his affairs is not a sign of magic; rather, it is a sign of filial piety, which is commendable.