The stuff about Marilyn Monroe is not credible. First of all, the article says "According to a biography of former lover Clark Gable..." and they link to an article
in which we learn that the biography says that Monroe and Gable were not lovers.
Secondly, biographies about celebrities who died a long time ago are generally useless. The dead cannot sue, so they can make up whatever salacious bullshit they please. Often, they don't even bother citing sources. Just look at the
Amazon reviews of this book in question.
My friends: if you hear something scandalous about a dead celebrity, and its cited to some recent biography: keep in mind that it's about as credible as a Daily Mail article writing: "a source close to the actor told us..." Or even less so.
(And even some of it is true: as Adric pointed out, it's probably a symptom of her mental breakdown, and not her being disgusting. Clark Gable and Marilyn met on the set of The Misfits, her last film. At that point, she had severe drug addiction, and filming had to be stopped for a week to take her to detox. Plus, her marriage to Arthur Miller was falling apart. So, it's possible that by that time, she didn't take care of herself; but that doesn't mean she always behaved like this.)
As far as we can discern, the sole purpose of human existence is to kindle a light in the darkness of mere being.
--Carl Jung