MARIE OSMOND is opening up about the crippling depression she suffered from – and she’s confessed to an electric shock treatment secret!

“Marie’s depression got so bad at one point she feared her career would be over or she would kill her­self if she didn’t take drastic steps to cure her misery,” a source close to the Osmond family told The ENQUIRER.

“So she asked loved ones to check her into a mental hospital for treatment. Not a fancy rehab facil­ity – but an old-time mental ward with padded cells, straitjackets, restraints and electric shock treat­ments.

“Marie didn’t know what might happen next in her mind and wanted to be in a hos­pital that was fully equipped to handle anything.”

Electroconvulsive or electroshock therapy is an aggressive treatment for severely depressed or suicidal patients. It often works, at least temporarily, but one poten­tial side effect is memory loss.

“It was only the fear of being un­able to remember the lyrics to her songs onstage that made her change her mind about undergoing shock therapy and toughing it out on her own,” the source continued.

Now, the TV and Las Ve­gas singing star is baring her soul in an upcoming tell-all book with hopes that her heart-wrenching story will help other women over­come depression. But that may not sit well with the rest of her famous family, and the source says it’s al­ready driven a wedge between her and her Las Vegas performing partner, brother Donny.

The book’s topic is the mental illness of depression and how it can shatter families, but Marie plans to reveal everything about her life struggles, including a lot of things her family does not want exposed,” divulged the source.

In an exclusive investigation, The ENQUIRER has discovered that the singer is revealing:

  •  Heartbreaking details about her son Michael’s tragic suicide in 2010.
  •  The cheating that shattered her first mar­riage to Stephen Craig.
  • The abuse she claims that she and her kids suffered at the hands of her second hus­band, Brian Blosil.
  • Her nervous breakdown and attempted suicide with drugs in 1999.

“I’ve been through a lot – more than you know,” Marie said in a recent interview. “I’m writing a book about it right now.”

Marie triumphed over her de­pression to become one of the most popular, hardest working women in show business. She now has a new hour-long talk show, “Marie,” on the Hallmark Channel, regular Las Vegas performances at the Flamingo hotel with Donny, a line of dolls sold on QVC, books, handcrafting and her charity work with Children’s Mira­cle Network.

There is no publishing date set for the book, but Marie is said to be putting the finishing touches on it now.

“Her family will find a lot in this book to upset them,” said the source. “But Marie has told them, ‘I’m 52 years old and ready to let everyone know the real story about my life. It’s time to finally set the record straight.’ ”