Why is Hunter still alive?

Think about his life. Always had whatever you wanted. Given hundreds of millions of dollars for nothing. Born with a 9' schlong. Gets to have sex with whomever he wants whenever he wants. Drugs, all he can handle. I mean the man has everything he has ever wanted, except happiness. He seemingly leads a life of misery looking for happiness. Why hasn't he put that gun to his own head and hit the permanent delete button? It's the one chance he really has at doing something in his life that will benefit mankind.