So, why does God allow horrible things to happen to good people?

First off, when under trial, let no one say "I am being tried by God" For with evil thing God cannot be tried. Nor does he himself try anyone James 1:13. But each one is tried by being drawn out and enticed by his own desire James 1:14. So basically we do all these bad things to ourselves. The reason why Jehovah allows all this to happen to us is to prove that mankind cannot rule himself. See when Adam and Eve rebelled against God, they basically said "We can rule ourselves". Now Jehovah must prove that we cannot.