I think this entirely depends who you are talking to and what culture you are in. In the US, this word could be used towards your close friends as a joke. Males can say this to males as a way of being funny, but typically it would be more common amongst females. I would say no when it comes to women using this word aimed at men. That would be more unusual, but anything is possible. This is a very strong word, and it is not appropriate for a man to say this to a woman.

Uh, no. I think you've misunderstood something here: "between friends" is not a simple concept, and calling a guy "bitch" just because you and he are friends doesn't work automatically. You would probably lose a friend and earn a punch in the head.

No