Love Marriage , But Girl's Parents not ready and Pressured girl not to accept my proposal of love marriage as she loves me too

Hello,
I m 23 Years Old Mechnical Engineer and I love a girl since 5 years who is now 20 Years Old and We want to do marriage with our own decision .
I initially tried to talk with her mother and after that with their Father. I talked with her mother and rest of ladies in her house but her mother didn't think and started to abuse me against my caste and over all. She is Brahmin (Dubey) and wants to marry with me but she is not open to speak with her family as she scared of getting killed by her father if he listens this.
My parents are ready to accept her, and said to convince her father and mother but I tried to talk with her mother, but by taking with her Mother only the condition is critical .
if I talk with her father than there may be worst condition for girl.
So What I should do in this situation ?kindly suggest me as her marriage is fixed 2 months after with other guy.
please help me to get out of this.
Thank U And Hoping to get best suggestion .