08/28/2009 at 06:30 PM EDT
Plans for actress Kelly Preston to break her silence about losing her 16-year-old son, Jett, have been put on hold, PEOPLE has learned exclusively.
The actress, who is married to John Travolta, had agreed to speak
at the California Governor's Conference for Women hosted by Maria Shriver in October on a panel titled "Grief & Resilience" following Jett's sudden death
"It is with my sincere apologies that I must pull out from speaking at [the] conference. I am sorry, but I truly believed that I could do it," Preston tells PEOPLE in a statement. "Otherwise I never would have said that I could. But I am still deeply in the process of healing, and it's just too soon."
Shriver, who just lost her 88-year-old mother, Eunice Kennedy, on Aug. 11, and her uncle, Sen. Edward Kennedy, who died Wednesday
, completely understands Preston's position.
"I know how hard it was for Kelly to make this decision and she has my complete support and understanding. Everyone has their own path to healing and their own timetable for grieving," says Shriver in a statement. "Kelly's presence at The Women's Conference will be missed, but the main stage conversation on grief and resilience with Elizabeth Edwards, Susan Saint James and myself will continue as planned. Having just lost my own mother and my uncle, I believe it's an important and meaningful subject because loss and grief will touch everyone at some point in their lives."
The Conference for Women
will be held Oct. 26-27 in Long Beach.