Love and hate have always existed and will exist, it is like the existence of day and night. The more love we give around us the more we will get it back. It is necessary to learn to give love and it will become more.
In fact, you are wong.
If you read Bible and other holy books, you will find out aboput origin of evil or hate.
In the beginning, first human ancestors, Adam and Eve, lived in the ideal world, Garden of Eden, blessed with God's love and goodness.
They made mistake, separated from God and evil enter the world.
So, evil come to the world because of human mistake.
We, humans, have free will and are always free to choose between good and evil, love and hatred.