A handwritten Marilyn Monroe letter detailing her suicidal thoughts is set to be auctioned off online in May (13).

In the undated note, addressed to famed acting teacher Lee Strasberg and penned on Hotel Bel-Air stationery, the tragic movie star reveals she is losing the will to live.

She writes, "My will is weak but I can't stand anything. I sound crazy but I think I'm going crazy. It's just that I get before a camera and my concentration and everything I'm trying to learn leaves me. Then I feel like I'm not existing in the human race at all."

The Some Like It Hot beauty died from a drug overdose in August, 1962.

The letter is estimated to fetch between $30,000 and $50,000 (£18,750 and £31,250) when it goes under the hammer at the upcoming Profiles in History sale, but Monroe's note is not the only top attraction at the auction - another undated missive from John Lennon to Paul MCCartney and his first wife Linda is also expected to be a big draw.

The typed two-page letter reflects the deep tensions between the two Beatles, with Lennon writing: "Do you really think most of today's art came about because of the Beatles? I don't believe you're that insane - Paul - do you believe that? When you stop believing it you might wake up!"

That note, thought to address problems in their relationship around the time of the Fab Four's formal break-up in 1971, is expected to sell for at least $40,000 (£25,000).

The mementos are just two of the 250 letters and documents being put up for auction by an anonymous American collector and some of the items will be put on display at Doug Elliman's Madison Avenue art gallery in New York between 8 and 16 April (13).

The Internet sale will take place on 30 May (13).