Didn't Mabel have a sad life...? But during that era a lot of Charlie's co-workers and friends died young.
Yes, the last few years of Mabel's life were very sad. The scandals involving the deaths of William Desmond Taylor and Courtland Dines had a detrimental effect on her career, as well as her health. She was also affected by the multiple trials of her friend Roscoe Arbuckle. Mabel was so talented and died too young. Charlie outlived many of his friends and co-workers, and even one of his wives (Mildred Harris). I believe this was due to his abhorrence of alcohol and the fact that he managed to avoid any kind of drug use. He was a smoker but quit sometime in the early 1940s. He exercised regularly and was in great shape up until the last ten years of his life.