Hate is an attempt of destruction.
Surely you have heard the saying "Keep your friends close and your enemies closer"? Well, hate fails to follow the essence of this proverb.
If you are trying to destroy something and you do not Love it, your options of destruction are very limited. Without Love there is no connection between yourself and the object you hate. Because of this, the thoughts of destruction do not reach their intended target and stay within yourself. Here they fester, destroying you instead.
Developing an attitude of hate cuts you off the world, and to replace these lost connections, various delusions have to be developed, which in turn cut you off even more, and so on.
It's a vicious circle.
The best way of dealing with hate within yourself is to realize that hate is an inefficient.
If you truly wish to destroy something, you have to learn about it, understand it, empathize with it, and Love it. This gives you the power to destroy what you Love.
If this process makes you realize that you do not wish to destroy anymore, then it was worth it, and the feelings of hate vanish.
If you have gone through this process and you still choose to destroy, you are able to do so clearly, efficiently and without regrets.
Going through Love to destroy something instead of blind hate makes you see just exactly what it is that you hate.
For example, if you hate a person and you learn to Love that person, you will realize that it is not the person you wish to destroy, but rather some of their behavior patters or your own buried fears which are somehow brought up at the sight or though of that person.
If destruction through hate is like burning down the house, destruction through Love is like making a surgical incision in order to heal.
Destruction is a valuable tool. Hate is the inability to wield that tool properly.