Life itself is not evil and the operation of the Laws of Karma are not evil operations, looking to even a score. Karma is a Law that teaches souls how it feels to do an act for or against another soul, thus balancing our actions with the appreciation of learning what it feels like to do unto another, good or bad. It is up to us humans to learn from our good and bad acts to either repeat them endlessly or not, to live in harmony or not.
The important thing to remember is that God, Spirit, life itself has no evil or malicious intent. It is only humans who are evil and have malicious intent. God, Spirit, life doesn't think like humans even though humans try to personify everything. Life may seem unfair and chaotic but it is not malicious. It just is!!!
This perspective is a critical one to understanding life. God is not mean and vengeful. God has given humans free will and it is humans who are mean and vengeful. How karma plays out is not an evil system looking to get even. It operates with energies that strive to maintain a balance, a harmonic state of affairs in the Cosmos. It is not logical or linear. It is meant to teach. How does it feel to kill another? The Law of Karma will bring that killing to you to show you how it feels that you may consider not doing it again to another. It's up to you to get the message, to learn from your actions.
Consider this concept when you see terrible things in the world and ask, "Where is God in all this suffering? Why does he let these evil things happen?" Just remember that God is right here allowing our free will to do these evil AND good things that we may expand the awareness of our souls, that we may grow to be beings of harmony. The operation of free will and karma may seem horrible to our rational, human minds but it is the way Spirit works. Spirit allows you to experience your evil, malicious or good intent without interference.
To this I say, take more responsibility for your actions, be more conscious of your actions, your behavior and your intent. It is you that perpetrates evil and good, not God, Spirit or life.