Marilyn Monroe is a key figure. Her story is full of sadness. She was used by the Hollywood system and had a hard time in her personal relationships. Then there's Charlie Chaplin. He had his own set of problems, including issues with the authorities over his political views which led to him being exiled from the US at one point.
Orson Welles is well - known in sad Hollywood stories. He had trouble getting his later projects funded and faced a lot of resistance in Hollywood despite his early success with 'Citizen Kane'. His creative vision was often stifled, and he struggled in the latter part of his career.
Buster Keaton also had a sad Hollywood story. He was a brilliant comedian but lost control of his career at some point and faced financial difficulties. Greta Garbo is another. She was a reclusive star, and her withdrawal from Hollywood was also a sad aspect of her story. There were personal and professional factors that led to her retreat from the limelight.