Why is it horrible? Well, because it eats its "host" from the inside out. Its like a virus or the plaque. It starts out barely noticeable at first, but then it festers, takes over, until finally it actually begins to consume the person.
Here is the real kicker........the person that they hate....probably doesn't even care that they hate them. It doesn't effect them not one little bit. More than likely, they will think it is funny. So who is it really hurting? You. Is it worth it? No.
How do you get rid of hate? That part is easier than you think. You have to learn to let it go. Like water off a ducks back. Let it slide off of you before it even gets to the point where it starts to be your ever waking thought.
Good advice.