A renowned Holocaust survivor and her husband made the decision to end their lives with assisted suicide, only letting their loved ones know with an email sent out after their deaths.

Ruth Posner was just a child when she survived and escaped the Treblinka concentration camp in Poland with her aunt. She was on the run for three years before settling in the United Kingdom. Later in life she became a successful actress, dancer, author and Holocaust educator. She married her husband Michael in 1950 but the couple faced tragedy in 1998 when their only child, son Jeremy, died at age 37 during recovery from heroin addiction.

Last month, on Sept. 23, Posner, 96, and Michael, 97, ended their own lives. They let their family and friends know of their decision in an email, reviewed by The Times. “So sorry not to have mentioned it,” they wrote, “but when you receive this email we will have shuffled off this mortal coil.”

“The decision was mutual and without any outside pressure,” the email said. “We had lived a long life and together for almost 75 years. There came a point when failing senses, of sight and hearing and lack of energy was not living but existing that no care would improve.”

“We had an interesting and varied life and except for the sorrow of losing Jeremy, our son. We enjoyed our time together, we tried not to regret the past, live in the present and not to expect too much from the future,” they ended. “Much love Ruth & Mike.”

Posner and her husband did not have any terminal illnesses but reportedly wanted to die together. The couple ended their lives after traveling from their home in London to a clinic with Pegasos, an assisted dying nonprofit organization in Basel, Switzerland.

Assisted suicide has been legal in Switzerland since 1942, according to Dignity in Dyinga British organization. ​​It’s different from euthanasia — which is illegal — because the patients themselves administer prescribed drugs to end their lives, rather than a doctor.

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Sonja Linden, a playwright who knew the couple for 30 years and received their email, told The Times that Posner was “frail” and her husband had vision loss and hearing problems. However, they both were “intellectually very well.”

“This was a decision they made together some time ago that they wanted to die together,” she explained. “They made an arrangement to go to Switzerland a year ago. We did not know they had actually gone until we received the email, which is sad as we wanted to say goodbye.”

“They had such a lovely flat packed with art and books and I can’t imagine them not being there,” she told the outlet.

Linden added that the couple was simply “exhausted” and felt like it was their time to go.

“They thought this was a positive decision and it helped them in their later life. I did not try to stop them,” she said. “I understood and supported their decision, but it was still a shock to receive the email.”

Following her death, the Holocaust Educational Trust paid tribute to Posner, describing her as “an extraordinary woman.”

“Although then in her eighties, she made it her mission to speak to as many young people as possible about her experiences during the Holocaust. She hoped that the leaders of tomorrow would learn the lessons of the past,” Karen Pollock, the charity’s chief executive, said in a statement. “Ruth was one of a kind. Full of charisma and warmth, she left an impression on everyone she met. We will miss her.”