Guys Don't Like Being Called A Bitch Because It Makes Them Feel Less Of Them Selves Just As It Makes A Woman Feel When They Are Called That.. So If You Wouldn't Want To Be Called A Bitch Why Would Yew Call Someone Else That.
Probably the same reason why anyone would get mad being called that. In any kind of context, that word is insulting. It really takes a blow at someone's character/pride.
