What if I said I was uncomfortable with my brother being gay?
Are you kidding me? Why would that make you uncomfortable?
It's just weird. I don't see him as a brother anymore.
I don't understand why his sexual orientation would make you that uncomfortable, it doesn't have anything to do with you. He can't choose his sexual orientation and the fact that you are judging him so harshly reflects extremely poorly on you.
I don't have to deal with it.
You do have to, he is your sibling and needs your support. If the tables were turned wouldn't you want the same thing from him? He needs you to be there for him because life won't be very easy for him.