Heresy is a word with bad connotations, sure. But do you know where the word comes from? It's derived from a Greek word meaning "to choose." A heretic, simply, is a person who chooses what he or she will believe, base a life on -- instead of blindly following what someone else dictates to be required.
That freedom of thought, belief and action is threatening to the powers that be in any dogmatic religious system. It leads people to ask "Why?" when told something ridiculous -- and if the answer isn't satisfactory, it leads to a loss in attendance and offering money. Thus the freethinker, the heretic, is vilified as a matter of the church's self-preservation.
Unfortunately, when it comes to dealing with those closer to us than the heads of whatever religious institution we've left, there is more than money or political power involved -- there are real and very high emotions involved. Breaking free from a belief system is hard enough -- even if you remain in the same religion, just moving to some branch less dogmatic -- but dealing with friends, lovers and family takes the concept of "dicey" to a whole new level.
To my way of thinking, there are three levels of difficulty to dealing with believers:

Let me illustrate where I'm coming from in each of these three categories.

Some situations do require making a stand for one's beliefs, or lack of them. And in those cases, stand tall. Stand proudly. You have used your mind and your heart to lead you to this most difficult of all decisions -- to live without fear, without an emotional crutch, without your decisions made for you, without someone telling you what to think every minute of your life. That's something to be proud of.
Just remember, there's no need to lose your cool. If you get mad at the other person, you've lost the argument, even if your reasoning is the soundest the earth has ever seen. Because if you get rude, or angry, or upset, the believer will think, "Ah, ha! Without God, there is nothing but misery!"
Nothing does the cause of atheism more harm than an angry, bitter and rude atheist. For all the good work that Madalyn Murray O'Hair did to end unconstitutional intrusions on our rights, she is not the best P.R. for us. Do we want people to think we're all cranky and rude and confrontational? I daresay that a lot of us just want to be left alone.
To that end, I think we do better to emulate Laurie Anne Gaylor and Dan Barker of The Freedom From Religion Foundation,a married couple who seem to be happy, charming, well-adjusted, and the ideal neighbors. While they are both held in high esteem by the atheist community, I had never heard of them until I became a freethinker... and I think that's a very important difference.
Dan Barker and Laurie Anne Gaylor don't act like they're looking to make as many enemies as possible. Madalyn Murray O'Hair was the most hated woman in America. Which model would you rather follow?

(This is adapted from a lesson I gave during the Unitarian Universalist Student Association's Spring Break retreat this year.)

God Is Dead -- Now What?
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