Who says who marriage is to be defined by and how is it to be defined? When opposite-sex couples go to get married, no one asks them if they are straight. Marriage is not about being straight or gay. Marriage is about joining one's life with another person for mutual benefits of many sorts, chief among them being companionship, and personal and financial support. It is not about sexual orientation and it's not necessarily about sex at all.
Legal same-sex marriage would not burden religion nor would it demean holy matrimony. Legal recognition of same sex marriages would not give any sort of burden on religion. Ministers, priests, rabbis and other religious leaders who are permitted to perform such marriage ceremonies of holy matrimony are not required to perform marriage ceremonies that conflict with his religious beliefs. The fact that these two are two separate ideas is clear when one realizes that not all marriages are performed in a church, or by religious authority. A justice of the peace can perform a legal marriage with no accompanying ceremony of holy matrimony. It happens all the time. Same sex marriage is only about legal marriage.
Same-sex couples don't provide the right environment in which to raise children. The fact is that many gay couples raise children whether they adopt or occasionally their own children from failed heterosexual relationships. It's been proven by scientific studies that the outcomes of the children raised in the homes of gay and lesbian couples are just as good as those of straight couples. What makes the difference is the love of the parents, not their gender. Gay people are as capable of loving children as fully as anyone else.
Our country is a country of liberty and justice for all; it's time we honor that. Let's get over our irrational reasons, based on ignorance and faulty assumptions, and honor our society and what we stand for. Let's legalized same-sex marriages.