The concept of "preparing for death" is alien to the Jewish tradition. Psalm 71 emphasizes retention of hope: "cast me not off in my old age when my strength faileth, forsake me not... But as for me, I will hope continually". Hence many sources suggest that it is not in the dying person's interest to disclose the nearness of death.
We deny death because it takes all our intelligence and all our heart to understand death.
Like a hen before a cobra, we find ourselves incapable of doing anything at all in the presence of the very thing that seems to call for the most dramatic and decisive action. The disquieting thought, that stares at us like a fact with a freezing grin, is that there is, in fact, nothing we can do. Say what we will, dance how we will, we will soon enough be a heap of ruined feathers and bones, indistinguishable from the rest of the ruins that lie about. It will not matter in the slightest whether we met the enemy with equanimity, shrieks, or a trumped up gaiety.