Here's the money quote. If we abhorred racism enough to force those with religious principles against it to integrate, which we did, we don't really have a logical reason to refuse extension of those same protections to other groups.
I'm not drinking the homosexual koolaid you're serving up. Who people are and what activities they engage in and or promote are not one and the same thing. One can love the sinner while hating the sin. There is such a thing as just discrimination.