How Bishop Fulton J. Sheen ended his life is shrouded in silence, for whatever reason. It would seem he could easily have written a book in retrospect before he died, but he would have had to seek out some way of getting into sympathetic hands without his overseers finding out about it.
A woman said she met him on a public train shortly before he died, and he was not looking well. She related that Sheen had told her that he regretted going along with the popular revolution at Vat.II and its aftermath, and that he wished he had held on to precious traditions that had been set aside, including the Traditional Latin Mass and sacraments. But the spirit of revolution was very strong and he had been swept away like so many others, and now (then) it was too late for him to do anything about it.
He had once been the foremost spokesman for the Church in America with his popular TV show, but after the revolution dug in, he had lost his place of prominence, and no longer was recognized by the new generation of so-called Catholics. He had no way of getting his message out and the revolution certainly did not want him to contradict any of its principles.