What does the word Bitch actually mean? If we look at the Oxford Dictionary definition we see that a Bitch is a female dog – a spiteful or unpleasant woman – or a person who is completely subservient to another: all of which seem to lean towards the negative.
The Urban Dictionary offers many an alternative definition; similarly pointing towards negative/unwanted relationships with people places or things. For example, a boyfriend who is his girlfriends “Bitch” because he does everything she says – the person [unwontedly] squished in the middle seat of car – or generally excessive whining, often related to a female.
From looking at these it makes sense that one would not want to be considered a bitch or have the word thrown at them in an argument or discussion as it appears as a damming and negative label.