h8.

From differences... and similarities.
You hate someone who's different. He/she might be unique in their own ways, but in any case it's one that you don't like. And you can also hate someone, just because they're like you. When they carry the things that you do, say that words that you speak. You hate it.

From lies... and truth.
Let's face it. No one likes liars. There is always this clear distinction of white lies and lies, well supposedly, but it doesn't change the fact that it hurts just the same. And we can hate someone just because they spoke the truth - like how they left was to make you happier. The golden classic.

From hatred... and love.
Hatred deepens with every additional unit of hate. And whoever coined the term "Love-hate", must have been a genius to see how this two extremes are never that far apart.

It's surprising how people learn how to hate.