Ok, so Biblically, God created the world, then rested, and Adam and Eve screwed up mankind's automatic chance for immortality by eating the forbidden fruit, encouraged by Satan. God created Satan, so therefore, God created evil. Or did he?
At this point in time, I'm thinking that God AND Satan, worked together to create the universe. Either purposefully or accidentally. Just as there has to be light in the universe, there has to be darkness. Just as there's matter, there's anti-matter. Good and Evil. Thus the never ending struggle.
Where do humans come into the picture? Perhaps we're just the bastard creations of both. Each individual, just pawns in Their game of good and evil, and the never ending struggle for superiority.
Both sides would be happy. Evil would be happy just fighting (even itself), and Good would be happy, because it would have something to defend (either love, happiness, or both). The weapons would be different, but the fight the same.
Either that, or everything I just typed was complete BS. Which is more likely to be the case. :)