Parents againts inter-religion marriage

Hi, I'm a 24 year old Hindu girl growned up from a middle class family. I fell in love with the Muslim guy during our college days. It is almost 6 years of our love my parents started searching for a groom. I have an elder brother he is the person who supports financially for my parents. he also got married with a girl different from our caste(inter-caste marriage). Now, when i said my parents that i love this Muslim guy they are strongly opposing saying that we will never ever agree to this marriage. my father threatens me that he will die if i don't listen to him and marry someone he shows. in my boyfriends family they are saying we will accept you only if your parents agree. me and my boyfriend don't want to run away and marry without parents approval we are ready to wait how many years it takes. My only problem is my dad threatens me that he will die if i don't agree to his words. what shall i do for this ? parents and my brother are not at all ready to listen to me. please help ?