Helena, Mont. – "Superman" actresswas ruled as suicide, and her daughter said Wednesday it was a relief to finally learn the truth. Kidder, who played Lois Lane opposite Christopher Reeves Superman in her most famous role, was found by a friend in her home in Montana on May 13th.
At the time, Kidder's manager Camilla Fluxman Pines said Kidder had died peacefully in his sleep.
A statement released Wednesday by Park County coroner Richard Wood said that 69-year-old Kidder had "died as a result of a self-inflicted drug and alcohol overdose" and that no further details were released.
Maggie McGuane, Kidder's daughter of ex-husband Thomas McGuane, told Associated Press in a telephone interview that she knew her mother had died of suicide when the authorities took her to Kidder's home in Livingston, a small town near the Yellowstone National Parks, brought.
"It's a great relief that the truth is out there," she said. "It's important to be open and honest, so there's no cloud of shame in dealing with it."
Kidder's death is one of several high-profile suicides this year, including celebrity chefand fashion designer .
McGuane noted that Montana has one of the highest suicide rates in the nation, prompting people with mental illness to seek help.
"It's a very unique kind of grief and pain," said McGuane. "I know how many families in this state go through that, I wish I could reach each one."
The actress was shocked by struggles with bipolar disorder in the 1
Kidder was involved in a car crash in 1990, which caused her indebtedness and led her to use a wheelchair for nearly two years.
Kidder and Reeve appeared in four Superman films between 1978 and 1987. In 1975 she appeared in "The Great Waldo Pepper" with Robert Redford, in 1973 in Brian De Palma's "Sisters" and in 1979 in "The Amityville Horror".  Later she starred in small films and TV shows until 2017, including "RL Stine's The Haunting Hour." In 2015, she received the Daytime Emmy Award for her role as a leading actress in a children's series.
Kidder, born in Yellowknife, Canada, was a political activist arrested in 2011 in Washington, D.C. for the proposed Keystone XL pipeline from Canada's oil sands.
Her last years were affected by conflicts with people who did not have the happiness she brought to her home. Between August 2016 and their death in May, the authorities were called 40 times to their house for reporting on attacks, theft and other riots, according to police records that were made available to the AP at the request of the AP.
The calls include ambulance responses five times in seven months, including at the time of their death.
Joan Kesich, a longtime friend who found Kidder's body, said Kidder was fearless and always told the truth, regardless of the consequences.
"In her last months she was herself – same love, same energy," said Kesich. "The challenges she had were very public, I want her to know that she's out there because it was glorious, she really was a blazing energy."
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