I've always felt that everyone has a right to believe whatever the fuck they want, just don't push it on me. I would just tell them something like that. Don't try to push your beliefs, or lack of, in them because then you'll be just like them. Just tell them you're happy the way things are and to knock it off....in a nice way because they're your friends. True friends wont care what you believe. If someone told me I was nothing without god I'd tell them to fuck off. It is insulting.
binny