Actually I was the same (while I was running a Windows box). I used to work for an anti-malware company too, and my experiences there pretty much agrees what everyone says about Norton / etc...

I don't open attachments from strangers, I don't have warez on my computer, and I call / confirm when I get a word doc. (It doesn't matter because I do the conversion on googledocs anyway).

I know not everyone is fortunate enough to do all of that, but it is entirely possible to avoid viruses if one really wants to.