Anyone who views abortion as more socially corrosive than gay marriage needs to update their priors in the face of recent historical evidence. Abortion is bad and kills babies, but hypocrisy surrounding life and whose lives are and aren't valuable is a pretty normal if unpleasant feature of society. Gay marriage redefines one of the most ancient and universal human institutions, the one which produces new life, and completely separates it from that purpose by expecting everyone to pretend poopdick is every bit as good and valuable. "Her wife" gives way to "her penis," and pretty quickly society becomes completely unmoored from reason and reality.