No, of course not. We (secularists, not "Christian-haters") don't need to amend it, we just need the Supreme Court to interpret it differently than in the case you've cited. They've probably done so much by now, it having been 100+ years since that case and whatnot.
Republicans who want to restrict gay marriage are doing so the right way, by promoting an amendment to the constitution.
Those on who "interpret" our "living Constitution" to make it mean something it never meant are the same leftists who "interpret" the Second Amendemnt as not applying to individuals. They are engaged in a war against the Constitution and and are enemies of the Republic.
Leftists just can't admit that what they believe is rooted not in US history and tradition, but is rather an alien socialist ideology very much at odds with the establishment of this Republic under God, so they have to try to rewrite history.