Death isn't the worst thing that can happen to us—
Until we figure this out, God will appear cruel and mean. Unless we believe Jesus when He says that He goes to prepare a place for us, we will have only this life to "look forward to" and thus cling to it with desperation and, if we are disappointed in this life, we are tempted to become bitter toward God.
If we're going to wrestle with this idea, we have to go back to Genesis 3 and the introduction of death. Years ago I wrote a short story about the Fall (you can read it here) - how could Adam and Eve be so tempted? How could Adam and Eve, experiencing direct contact with the Creator, end up doubting Him and listening to the deceiver?
You realize how easy it is for us to read Genesis 3 in punitive terms: and God said, "If you disobey me, I'll kill you!" and it's completely over-the-top, an out-of-proportion overreaction.