The good thing is, being same sex oriented is becoming something that is widely accepted. So really all you can do is say "Yes I like women, deal with it." Anyone that has the guts to bully you for who you love can easily be reported to adults or figureheads. As far as you friend that identifies as anti-gay, if they cannot accept you for who you are, regardless of your preferences or life-style, and would drop you that fast, she was never your real friend to begin with.