You are right about one thing: We do live in a world that's constantly torn by conflict, injustice and even death. And you're right also when you say that we're responsible for these things - because we are. Jesus said, "Out of the heart come evil thoughts, murder, adultery, sexual immorality, theft, false testimony, slander" (Matthew 15:19).
But God is not responsible for these terrible things - because the world was perfect when He created it - and so were we. The Bible says that after God created the world, "God saw all that he had made, and it was very good" (Genesis 1:31). God is perfect - and all He made was perfect also.
What went wrong? The problem is that Adam and Eve, the first humans, deliberately chose to turn their backs on God. God didn't make them like robots or puppets; they had the ability to choose between good and evil. And when Satan tempted them and told them that God was deceiving them, they believed him - and they sinned (see Genesis 3:1-13).
We'll never understand evil completely in this life; the Bible calls it a "mystery" (2 Thessalonians 2:7). But the most important truth about Satan and evil is that they were defeated, when Jesus Christ died and rose again. Is your faith and trust in Him? He alone has power over evil and death and Hell.