Individual moral views notwithstanding, freedom to choose ("discrimination") is our right, our privilege, and our duty.
MLK helped give discriminating (freedom to choose) a bad name. But we as individuals have every constitutional right to choose and discriminate however we want.
The only constitutional limitation on choosing or discriminating is prohibition of STATE SEGREGATION laws against blacks (14th Amendment).
There is NO constitutional limitation on individual discrimination AT ALL.
As far as the feds are concerned, a state can discriminate against gays or anyone else except blacks. It is up to the citizens of each state how they want to deal with their own freedom to choose or discrimination.
Bingo