My deepest fear is losing everything, but life. The people I know and love, the possessions I hold dear, "freedom", or control of my life (which I've almost lost as is), and all of that good stuff.
Death is death, it's just a permanent respite. But remaining alive with nothing, or little left, is my ultimate fear. Humans are often greedy, and I certainly apply to that. I don't wonder why losing everything scares me so much. I've already lost too much, losing just as much again will drive me to the brink of insanity.