So true. I once knew a girl who had been told that I called her a bitch and she came after me and before she beat me up, she asked if it was true. I said no. I called you "this, this and this" for these reasons, but not bitch, because that is a female dog (we were in junior high at the time), and I earned her respect and we ended up being quasi-friends after that. If I am not willing to say something to someone's face, I am sure as hell not gonna say it behind their back.
People who talk shit behind people's backs are truly cowards.