By Laura Zuckerman
SALMON, Idaho, July 18 (Reuters) - Freed war prisoner Bowe Bergdahl has not yet reached out to his parents who campaigned hard for his freedom and who hold out hope he will eventually contact them once fully recovered from trauma inflicted by his Taliban captors, a family friend said on Friday.
Stefanie O'Neill, who is in regular contact with Bergdahl's mother, said the U.S. soldier's parents were strained both by their son's silence since his May 31 release and because of death threats being investigated by the FBI.
"Bob and Jani are under more strain than ever, but they are trying to be patient," O'Neill said of the couple, who continuously pressed their son's case with the Obama administration.
O'Neill, whose friendship with Bergdahl's mother was forged by a rally she helped organize last year in the family's Idaho hometown, said Jani Bergdahl has sought to put on a brave front.
"She puts on a smile but you can tell she's suffering in all this," O'Neill said, without offering an explanation for why Bergdahl had not spoken to his parents. "She doesn't understand - how could any mother understand? - why her child literally won't take her phone calls."
Bergdahl, 28, was freed in exchange for five Taliban prisoners held at the U.S. detention facility in Guantanamo Bay, Cuba. Critics said the Obama administration paid too high a price and questioned if Bergdahl deserted his combat outpost before being captured.
This week, Bergdahl was assigned to a desk job at a Texas military base after completing counseling and a reintegration program and as the Army investigates the circumstances that led to five years of captivity.
A friend of the younger Bergdahl, whom he first met in Idaho 14 years ago, said she visited him in Texas and had arranged for a civilian attorney to represent him amid the Army probe, but that he had not reached out to his parents.
The Bergdahls did not respond to a request for comment. A senior Army official confirmed Bergdahl had not spoken with his parents during his reintegration program, but said his contacts were no longer being tracked since his return to regular duty on Monday.
Jeffrey Moore, executive director of the Robert E. Mitchell Center for Prisoner of War Studies, a U.S. Defense Department program, said a minority of American servicemen taken prisoner during the Vietnam War chose not to contact their families after release in circumstances possibly stemming from estrangement preceding capture.
He said he could not speak to Bergdahl's experiences since he has not met him. But he said long-term studies of 660 Americans taken captive in Vietnam showed most were at some point told lies about their families, fellow soldiers and their nation to force them to sign statements admitting to war crimes.
Servicemen whose relationships were troubled before capture found them complicated when they returned home, and Moore said odds were not high of finding sour milk had turned sweet over time.
"Absence does not always make the heart grow fonder," he said. (Editing by Cynthia Johnston and Eric Walsh)