How to get my family to talk to my brother even though he is gay?

My family is very large. I have 6 brothers and 5 sisters. So there is 12 children in my family including me. My parents are strict catholics and republicans. I am engaged and so is my sister. I have a brother who is a few years older than me. He was very different from others during his youth years and was teased. He never dated anybody and now he is 38 and he has came out as gay and says that he has always had a partner and they have secretly been living together in California and are going to get married. My parents were so angry and my father called him a fag and said he will burn in hell and my mother said that he would live his life a sin. My parents stopped talking to him and so has everybody in my family except for me. My brother is now hurt and he wants my family to accept him for who he is but besides me everybody is outraged and they call him fag and other offensive words and always bring in God. I got into an argument with my parents and they called me a B i tch, Fag enabler, and fag hag and are now ignoring me. Now i have no idea what to do and i need help to unite my family.