All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His Slave and Messenger.
It is not permissible for guardians, whether fathers or brothers, to harm the girl in any way, whether through physical abuse, verbal abuse, or any other form of harm. The girl is not obligated to endure such harm; she has the right to speak up and make it clear to them that this harm is not permissible. She can warn them of the punishment of Allah. If they do not desist from causing harm, she can seek the intervention of wise relatives or other righteous people to mediate between her and her family until they stop harming her.
If her family persists in harming her, she has the option to leave the house and stay with one of her mahrams (permanently unmarriageable relatives), such as an uncle or a paternal aunt, if possible without causing harm. If that is not possible, she has the right to leave the house and live independently if she is confident about protecting herself from fitnah (temptation). Some scholars have permitted a mature and responsible daughter to live independently if there is no fear of fitnah. Rawdat al-Talibeen by Al-Nawawi reads: “As for the female, when she reaches puberty if she is married, she stays with her husband. Otherwise, if she is a virgin, then she stays with her parents, or one of them if they separate, and she chooses whomever she wants to stay with. Is she compelled to do so? There are two opinions: One, yes, she does not have independence. The other, no, she has the right to stay wherever she wishes, but it is disliked for her to separate from them...”
However, these rulings assume that there is no wrongdoing or suspicion on the part of the girl. If there are valid concerns or accusations against her, the father, grandfather, or whoever is responsible for her marriage can prevent her from living independently and may bring her back into their care.
Regardless of the situation, the daughter has to maintain respect and kindness toward her parents to the best of her ability. The parents' rights are great, and these rights are not nullified by their wrongdoing or mistreatment of their child. Please refer to Fatwa 120947.
Allah knows best.