Have you ever been asked when you knew you were straight!?

Ok so my brother is openly gay, I have always known even when he was a very small child, and lucky for me I was the first member of our family he told because he knew I have an open mind and I am not a racist judgemental bigot. Unfortunately for him the rest of our family are very judgemental, very close minded, and like to preach from the bible only when it condems someone else. My dad is probably the worst. On a regular basis he says my brother has all that "hot sexy p**** right next to him yet he wants a dude! Nasty!" My brother brought his boyfriend over to meet my dad one day and asked me to go along with him for moral support and my dad started harassing my brothers boyfriend. Telling him he ruined my brother and hes a sinner and he is going to hell. Then he asked what made him decide to start chasing d*** at which point I stepped in and asked my dad when he knew he was straight? My dads response was "Ive always been straight! I aint no queer" so I explained to him that my brother has always been gay and no amount of belittle, degrading, or racial comments will change who he is. So now my family (my dad, grandma, and aunt) will no longer talk to me or acknowledge my exisistence, they no longer ask to see my kids, or even talk to my husband, yet they still talk to my brother. Not that I am necessarily upset because I hate my dad and grandma anyway, but doesnt that seem a little one sided?? Especially to turn on my kids??