i didnt know this
On April 10, 1994, shortly before the film version of his 1990 novel Leaving Las Vegas — starring Nicolas Cage and Elisabeth Shue — began preproduction, O’Brien’s tale ended when he put a gun to his head and pulled the trigger. He left no letter, just an oddly romantic, bender-to-oblivion book that was more autobiographical than anyone had imagined. It was, in effect, a 189-page suicide note...
https://ew.com/article/1995/11/10/john-obriens-bittersweet-departure/