Shakespeare's Macbeth - Fate is Unfair

After reading this climactic and literarily intriguing section of William Shakespeare's venerated play, Macbeth, I started to chuckle about the foolishness of Macbeth's actions. The play opened with Duncan's murder, for Duncan was too trusting in his seemingly loyal subjects, namely, Macbeth and Lady Macbeth. Later on, Banquo lost his life due to this immense trust in another, Macbeth. Finally, it is Macbeth now that falls after believing whole-heartedly in the witch's prophecies, for he …

…is stating that life is meaningless and irrational. Thus, I believe that since Shakespeare is expressing such a dark theme in his text, because one's writings are a window into their lives, as Arthur Paul Patterson's Passions of Prometheus states, and also because he suspiciously died on his birthday of a suspected poisoning, William Shakespeare can be seen as a depressed man, who, understanding this shocking theme of Macbeth, tragically ended of his own life.