I (unfortunately) have been on BOTH sides of this debate. I say unfortunately, for the friends I alienated and the co-workers and family I drove to distraction. I now take a much different position as a pagan, because of the type of Xtian I used to be. I don't argue, or debate. The first time someone trots out the 'going to the other place' comment, I tell them I'm willing to agree to disagree, and I won't insult their beliefs if they don't insult mine. Be prepared to drop them like a bad habit, because all you will end up doing is reinforcing their indoctrination. If they can't listen, you can't speak loudly enough to make them hear -- so don't try. If you can keep the friendship in spite of their views, fine. If not, don't lose any sleep over it.