How can I legally protect my girlfriend from forced marriage?

I have been in a relationship with my girlfriend for 5 years, but her family is not agreeing to our marriage, even though there are no caste issues. My family has also tried several times to convince them, but they are not listening. My main question is, how can I legally release her from her father's house if they try to forcefully marry her to someone else? What legal actions can I take, and what legal rights do I have over her until we get married? Can I file a writ petition for habeas corpus?