In slang, a bitch is defined as a "malicious, unpleasant and selfish person"
Most people have a set of people they can get along with, and a set of those that they can't. And for those that they don't get along with, they simply ignore or allow them to fade out of their lives until they no longer matter. That is perfectly normal, mature, and acceptable behaviour. Bitches however, insist on making life difficult for people they don't like, simply because they can, and it gives them pleasure to do so.
Unlike the non-bitchy, who use straightforward means to show dislike because they are nice, or too simple minded to resort to emotional manipulation, bitches can be extremely adversarial.
For most people, when other people cross their path, they complain about it, but they forget about it after awhile because they have goldfish memories. They gullibly assume that everyone loves them, which makes them endearing and frustrating in equal measure.
The thing about a bitch is, if anyone has crossed her path, she doesn't forget. And if she is unpleasant enough, she will continue to harbour ill will towards these people. The word bitch also means "female dog." But unfortunately, female dogs are actually lovable animals. They do not deserve this association. The variety of bitch I'm talking about, hell wouldn't have enough space to keep her. It's probably already overflowing with her kind.
A bitch will not openly show ill will. She will pretend to maintain cordial relations, but take digs at you on her blog, on facebook, around her friends who may happen to be your friends too, and in any other social media, basically in any way that allows her to attack you passively and aggressively so you know that the attacks are directed at you, and yet you are hard pressed to get the bitch to admit it. Because she is a bitch, she enjoys knowing that you are affected by what she is doing. It is this pleasure in causing hurt and suffering to others that I find absolutely disgusting.
When confronted, this variety of bitch also has a way of playing the victim card, so it always looks like you're the one who's being mean. You can't attack her without looking like the bad guy, simply because the bitch is attacking you indirectly.
There is only one way to kill a bitch, and that is to ignore her. Ironically, all bitches have this weakness, and that is they actually crave the attention that comes from knowing you are affected by them. All bitches are just sad attention whores. Once people get tired of the games they play, they will literally find that they have run out of listening ears. It gets a little harder with facebook because there is always an audience, but eventually, people will find more interesting things to follow.