I don't believe marriage is necessary of course. I don't believe in adultery or that sex before marriage is a sin. But marriage has benefits. And some people like the idea of it and the romanticism of it. Some people think that it is a celebration of love.
However, I have been told time and time again by some Christians I know that marriage is a religious, Christian union between a man, a woman, and god and that non-religious people shouldn't get married. I was told that the state has no business marrying people and that the only institution that should is the church.
I believe that anyone who wants to get married should. I don't believe that being an atheist (or gay for that matter) should prevent people from getting married. I don't want this to be a gay marriage discussion, however. I simply want to discuss the idea of marriage and debunk these people's arguments. Christians like to have the monopoly on marriage and believe that they own it but they don't.
How does the non-belief in a god or gods even matter when it comes to marriage?!