Suggest me sir

Sir i want to take action against my cheated girlfriend. I love each other so much and want to live with each other. She loved me so much. Once her elder sister knew about my relationship by her. Then she called me and told not to talk with her. And also her sister told her not to talk with me.Her sister told me about the dissimilarities in caste. From then she didn't contact me . I was trying alot to talk her but she didnot. At that time my examination also starts and a severe operation also on my brain. Then also she didn't talk with me. .. I m so much mentally depressed and for that i didnot concentrate on study due to mental harassment and i failed also in examination. So i decided to talk with her parents after her study as i wouldn't want any disturbances in her study. . Then one day i told about our relationship to her parents . I tried to understand them about my feelings but they didn't. Then she also opposed me and misbehaved me . . So i want to case against her as she was 21 years old , she knew that we r of different caste then also she loved me and spent many times with me and promise to marry with me. . If she don't want to marry with me so why she loved me spent time with me and why she promised to live with me .When she spent time with me and in relationship, where was her parents and sister and brother. Why they didnot oppose her to talk with me. Now when she love me promise me spent time with me, why they interfered in our relationship. Why they give permission her daughter to talk with me. . Now she also refused . She also cheated me. So i case against her and against her family. . So sir what is the procedure to case a file .I have many photographs all WhatsApp chats messages many gifts of her. And what will the DHARAs against her and her family. What will happen.