Marilyn had many mental disorders varying from bipolar disorder to manic depression to everything in between. She was a tragic case, and one night she crashed and ODed on sleeping pills. There has been on going debate for over 40 years that she didn't kill herself, but was indeed murdered, but in most cases it is accepted that she simply crashed and committed suicide.
I believe the date was August 4th. She was found by her roommate, holding a telephone. She was rushed to the hospital, but she never regained consciousness.
Many people say that several different men were involved in her death, but people also say that Princess Di's death wasn't an accident.
Conspiracy always surrounds the death of a young, beautiful, famous woman.