Superman star Margot Kidder passed away in May and now the cause of her death has been revealed as an apparent suicide. Park County coroner Richard Wood recently released a statement saying that Kidder "died as a result of a self-inflicted drug and alcohol overdose." No further information regarding her passing is going to be released.

Margot Kidder, who played Lois Lane in the 1978 blockbuster superhero movie Superman, was discovered by a friend at her home in Montana on May 13. The state has one of the highest rates of suicide in the nation. Kidder had her share of troubles and dealt with bipolar disorder throughout her life, and was diagnosed with manic depression in 1988. This ultimately led to her having a breakdown in 1996. Kidder even spent a brief time being homeless following her breakdown. In the years that followed, she advocated for doing away with the stigmas that surround mental health issues.

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Maggie McGuane, Margot Kidder's daughter from her ex-husband Thomas McGuane, said in a new interview that she knew her mother died of suicide at the moment local authorities took her to Kidder's home in Livingston, a small town near Yellowstone National Park. McGuane says that she's happy the news is out there now as to not contribute to any shame that may come along in dealing with mental illness. Here's what she had to say.

"It's a big relief that the truth is out there. It's important to be open and honest so there's not a cloud of shame in dealing with this...It's a very unique sort of grief and pain. Knowing how many families in this state go through this, I wish that I could reach out to each one of them."

Margot Kidder was 69 at the time of her passing. She had acted in smaller movies in recent years. However, she is best known as Lois Lane in the Christopher Reeve Superman movies. She starred alongside Reeve in four Superman movies between 1978 and 1987. She and Reeve remained friends until his death in 2004. Some of her other credits include Sisters, The Amityville Horror and R.L. Stine's the Haunting Hour, which earned her a Daytime Emmy. Joan Kesich, a longtime friend who discovered Kidder following her death, had this to say.

"In her last months, she was herself, same kind of love, same kind of energy. The challenges that she had were very public. I want what I know about her to be out there because it was glorious. She was really a blazing energy."

2018 has seen several other celebrities take their own life. Celebrity chef and Parts Unknown host Anthony Bourdain, as well as fashion designer Kate Spade also died of suicide this year. Margot Kidder's last years were filled with trouble. Between August 2016 and May, local authorities were called to her house 40 times on reports of people trespassing, theft and various disturbances. These were as a result of Kidder taking people that were down on their luck into her home. In addition to her career as an actress, Kidder was also a political activist who was actually arrested for in Washington D.C. in 2011 while protesting the Keystone XL pipeline. This news comes to us courtesy of the Alternative Press.