No. Religion does not own the concept of marriage or the word either. It’s not just about same sex couples. There are millions of straight couples in this country who have been married by the government without having to seek the permission of any church, and their marriages are just as real as yours. It’s been like that for a hundred years before we were born and nobody ever objected until they started talking about giving same sex couples the same opportunity. It’s not just a religious institution, and it hasn’t been for a long time.
Gay marriage is not the same as traditional marriage. With traditional marriage, you have biological children, grandparents and genealogies stretching back hundreds of years. With Gay marriage all you have is two gays cohabiting. Maybe they could adopt children, or be hetero for a moment and have their own, but their relationships have nothing in common with traditional marriage other than erotic love. In the long run, children will suffer and marriage will become meaningless. This will become the most destructive social change the world has ever seen.
I’ve been to a lot of weddings and they always talk about love and commitment but I don’t remember ever hearing children mentioned in the ceremony. Lots of straight couples can’t have biological children together. This doesn’t stop them from being parents and it doesn't stop same sex couples either. Their relationships have everything in common with traditional marriage other than biological reproduction. Nobody gets married just for erotic love. Gay people who are willing and ready to marry love their partners just as fully and deeply as you love yours.In the long run, children will not suffer in any way and marriage will be as meaningful as it ever was. Claiming that same sex marriage will harm traditional marriage makes no more sense than claiming that if I can open an Italian restaurant, the Chinese food in your restaurant won’t taste the same. This will be one of the most harmless social changes the world has ever seen.