How does King Lear act following the abdication of his kingdom?

It is frequently observed that when old men decide to make radical changes in their lifestyles it is often a sign that before very long they are likely to die. The decision to make the change, usually in hope of achieving more enjoyment out of their remaining years, is often prompted by an unconscious premonition that their lives are already nearly over. People sense when they are going to die. Radical changes in lifestyles, such as divorce, or losing a long-held job, or moving to a different city or a different country, can be dangerous for any man, as we are told by psychologists, but radical changes for old men can be fatal. It is a common occurrence for a man to reach the retirement age of sixty-five and then to die after only collecting his Social Security checks for a few short years.
As David Mamet has one of his characters say in his excellent play Glengarry Glen Ross, "A man IS his job." King Lear gives up his job as ruler of a nation but can't give up the belief and the feeling that he is still king. He doesn't realize that without his job he is nothing. And this inability to accept this fact is what leads to his death. He is on a path towards death from the moment he gives away his kingdom. He keeps asking others, in so many words, "Who am I?" He even asks Oswald to tell him:
O, you sir, you, come you hither, sir: who am I, sir? (1.4)
King Lear makes the radical decision to give up his kingdom, to give up his castle and the income from all his lands, and to spend his time hunting and feasting like a man only half his age. He does not realize the truth, which is that his life is already over. Shakespeare's play is about how one generation dies and another generation assumes their places. One generation creates and nourishes the generation that will displace them.
Parallel examples in modern literature would include "Sailing to Byzantium" by William Butler Yeats and "Crossing the Bar" by Alfred, Lord Tennyson. Willy Loman in Arthur Miller's play Death of a Salesman begins planting a garden by moonlight on the very night he is going to die. Willy has already talked himself out of his long-held job as a traveling salesman. Leo Tolstoy's beautiful story "What Men Live By" features a rich man who orders a pair of boots from a fallen angel who knows the rich man is fated to die that night. A similar theme might be detected in Tolstoy's "How Much Land Does a Man Need?" Tolstoy himself died in a railway station when he had made a radical decision to leave his home and family at the age of 82 without apparently having any specific destination in mind.