Then what is the way to do it? Roll over, play dead, and let the homosexual rightists and their minions have their way with us?
What third option is there, or do you prefer the second option, above?
Your whole argument is premised on one enormous false dichotomy. Only a short-sighted fool writes legislation into the Constitution, and it opens up a very nasty Pandora's Box.
Alternative #1: Get the government out of the marriage business altogether. You didn't need to ask permission from the government to get married way back in the day. It has been nothing but a disaster since it left the church and became what is primarily a government entitlement of sorts. All it does is give politicians a vehicle to do social engineering; great when your team is in power, not so great when Hillary is President.
Alternative #2: Let the States decide. Since gay marriage laws have failed spectacularly when left to the voters even in States like California, they won't go anywhere. The "full faith and credit" clause won't apply even if a couple States do pass it, any more than it does for most other things e.g. CCW.
Of these two more structurally correct alternatives, Alternative #1 is by far the most bulletproof of the bunch. Evil politicians can't abuse it, judges can't abuse it, and you don't engage in the profoundly stupid act of legislating in the Federal Constitution.
I don't need foolhardy conservatives jeopardizing the long-term situation in this country so that they can gain a short-term political "victory", particularly over such a nebulous issue. There are many ways to take the issue off the table for the homosexual lobby without doing something equally stupid in the opposite direction.