ilovelife, I'm going through the same thing. My parents are always trying to get me to believe in God. I'm an atheist and I've explained to them several times why I am, but they think atheism is so crazy and evil so its useless to argue with them. Take Ghostoker's advice. Most likely if they really are religious it will not work because they dont want you to go to hell. (I'm assuming they believe in hell). I mean, if I was a parent and thought my kid was going to hell Id never just say "You're an atheist? Thats fine."

So just avoid the subject of religion as often as possible. If they talk about God, just dont say anything. They'll probably want to believe you started believing again, even though deep inside they know you dont. But they'll be thankful you're not so anti-God that you will argue with them everytime they bring up the subject of religion.

I know its hard to be atheist and living with people who believe in God. But look around you. Most people believe in God and they always will, even people you love. I just remember that saying "Religion is the opiate of the people", and it helps relieve a lot of my anger towards people who believe in God.