Dr. Manuela Joannou is stepping down from her role as the medical director of a trauma program for military veterans and first responders in eastern Ontario amid public anger over her decision to place a registered sex offender as a peer mentor for a group of sexual assault survivors. CBC News revealed last week that Joannou failed to tell a group of 12 female first responders and Canadian Forces veterans with post traumatic stress disorder that they spent a six-day trauma retreat in July 2018 with a retired soldier who had recently been convicted in two different sexual assault cases. Seven participants who came forward publicly said they felt betrayed, violated and retraumatized to learn about retired major Jonathan Hamilton's criminal past on their own and were appalled that Joannou defended her decision when confronted. Joannou announced on Facebook Saturday she was leaving her role as medical director, but did not say if she would still be involved in running Project Trauma Support in another role. "I acknowledge that I made mistakes and fully take responsibility," wrote Joannou. "I am very sorry that this mistake has caused upheaval and I wish everyone well." "My sincerest wish for you all is that all will continue on in a path to recovery." Past participants told CBC News they are curious to see what role Joannou plays moving forward since she is the founder and operates the retreat on her own property in Perth, Ont. CBC News has sent Joannou a request for more information. WATCH | Sexual assault survivors stunned to learn peer mentor was convicted sex offender: Retired brigadier-general Paul Rutherford resigns The chair of the charity's board of directors also resigned Saturday. Retired brigadier-general Paul Rutherford issued an internal letter stating he was submitting his resignation "in light of the recent media reporting concerning the integrity" of the program. Rutherford came under fire by past participants for signing a letter with Joannou in response to CBC's original story that did not contain an apology for what happened. The letter also said that participants should not be speaking publicly about the program since it's confidential. "I sincerely apologize for any hurt that any program participants have felt," said Rutherford in a letter obtained by CBC News. "It was not my intention to cause any feelings of distress." Rutherford wrote he personally would have never allowed a convicted sex offender to be a peer mentor. He is now recommending new screening measures, including criminal background checks, he said. "With profound empathy and support for victims and survivors of any sexual harassment or abuse, PTSD, or moral injury, I resign my position as Chair," he wrote. Canadian Forces chief of rehabilitative medicine apologizes The Canadian Armed Forces' (CAF) chief of rehabilitation medicine, Lt.-Col. Markus Besemann, also left his role with Project Trauma Support in the wake of the story. Besemann had been volunteering with the charity since 2016 mainly by holding 2.5-hour lectures about physical emotional pain and suffering, CAF said. He had also suggested some of his patients take part in the program as part of their efforts to heal, said CAF. "I am deeply saddened to learn that in the process of attempting to help those most in need of healing, we may have contributed to their pain," said Besemann in a statement to CBC News. "I want to personally apologize to those impacted. I am truly sorry." Besemann said he has been treating survivors of sexual trauma for 32 years as a clinician. Donors cut ties with charity The series of apologies and resignations come days after the charity lost its funding from several large donors. The Mood Disorders Society of Canada severed ties completely and Veterans Affairs Canada said it will not provide future support. The Royal Canadian Legion also said it was astounded by how the situation was handled by the program's leadership and will no longer consider future funding. Female participants of Project Trauma Support in Perth, Ont., join in a group hug at the centre of a labyrinth. The charity is not funded by the Canadian Armed Forces.(Hallie Cotnam/CBC) True Patriot Love Foundation, another donor, said that the program has helped many people dealing with severe trauma and it will look for ways to continue to support it. "I am hopeful that True Patriot Love can explore ways to help the program move forward in order that it can continue to provide care to those who need it, while avoiding the significant errors your story refers to," True Patriot Love Foundation's CEO Nick Booth said in an email to CBC news. Joannou said family physician and ER doctor Dr. Rebecca Van lersel who has an interest in mental health will be taking over as medical director. "As we listen, reflect and work toward reconciliation over the coming months, I look forward to regaining the trust of our alumni, prospective cohort participants, and funders," wrote Van lersel in the social media post. The College of Physicians and Surgeons of Ontario (CPSO) investigated a complaint into the matter and determined in 2019 it was inappropriate that a convicted sex offender was peer mentoring sexual assault survivors. The CPSO said it had concerns about Joannou's judgment in this case and advised her to be mindful of her hiring practices in the future.