The trick is, that barring accidental death (including accidentally falling victim to someone elses intentional killing of you), you will stop wanting to live before you die. So take care of yourself, preserve your health, and enjoy your life -- by the time it's over, you won't want it anymore. So don't fear death; only fear harm in your life.

Also, remember that when you're gone, it won't hurt, and you won't miss anything. Everything in your life, from the worst torture to the most minor itch, hurts more than being dead.