Ever since I became sure of my stance, I have been a "loud" atheist on facebook and in real life.
Of course some of my friends don't like that someone is challenging their beliefs, but I've grown to feel some sort of apathy towards their feelings when it comes to faith. Every now and then I'll put an atheistic quote as my status. I also, as the thread starter mentioned, comment whenever I see something that has to do with religion on facebook. Be it a debate, a video or one comment. Some of my friends like it, and some don't.
What made me ease up with my negative comments about religion, was when my mom asked me to stop. Why? Because it hurt her feelings. I didn't really mind when my friends were annoyed with my input on facebook, because I knew that they were about as much a christian as I was. But when it was my mother, who is a 'true believer', I eased up. She is a peaceful christian, she has nothing against homosexuals, she's a doctor (which isn't exactly a job for the stupid), she's pretty much an idol, and I didn't want to hurt her.
Don't get me wrong though, I'm still a militant atheist, just not so much on facebook.
I am totally in the closet on Facebook but one of my Facebook friends who is 18 put a caption under her profile that said "fuck your religion". But I don't think you can have captions under your profile any longer and I don't think it gets any more offensive then that.
That's kind of like having a sign on your front door that instead of saying "no solicitation" it says "fuck your religion" lol. That's just too much but she is a funny one (the good kind of funny).
First off, I have two facebook accounts. One is work, my kid's friends, family, Xian friends, everybody but the really rude fuckers. I call it my PG-13 facebook page. Its not PC, but its pretty tame. 800+ friends.
On my NC-17 page, I speak my mind much more freely. Less than 100 friends.
I didn't proselytize much (in my mind) when I was a Xian. I ignore most Christian comments and posts, but get in my face and you will get it with both barrels. Occasionally something will rub me the wrong way and I will say something causing a shitslide. I will slam those who post intolerant bullshit on either account.
There is a time and a place for everything. I don't make a secret about being an atheist, but I don't walk around rubbing people's faces in it. I'm happy to have conversations with people if they are civil. I do post atheist links and articles on both accounts, but I don't overrun them. I'm not out to deconvert the world. Yet.
I'm sorry for your loss of your friend but at least it is a good sign that intelligence is poking its tender head into your Facebook.