Also, her substance abuse problems were also picking up, which made it hard to stay focused at work. She was hospitalized for a week in Los Angeles. They announced their divorce later that year.

On August 5, 1962, Marilyn died from a drug overdose. Arthur didn’t attend her funeral, noting, “She won’t be there.”

Source: https://www.distractify.com/p/arthur-miller-marilyn-monroe-relationship-timeline