Another "straw man" argument. The proper way to phrase this is that because the Republicans have attempted to block gay marriage, they have in essence, due to the ways our laws are worded, attempted to block gays from enjoying the same rights as heterosexuals. They do care about gays. They care to prevent them from enjoying the same rights as heterosexual couples by opposing the term "marriage" being used to characterize civil unions between to partners of the same sex. It's a legal issue in addition to an emotional one for gay couples. Many of our laws use the term married or marriage but do not specifically equate marriage to civil union, even though logically they are the same with regard to civil law.. Laws, however, turn on words; not logic. The Supreme Court seems to have settled the issue, nevertheless the Republicans can not claim the higher ground here.
Therefore, you are squarely against quotas and affirmative action. Right? Or infringing upon people's religious rights. Right?
Civil Unions can be marriage or could be marriage. All it takes is for the law to say so. Republicans believe in equal opportunity. Lefties try to get equal outcomes. An concept which results in some groups being penalized. Which you could easily deem discrimination.