Psychologists worry not talking about the hurt could be doing long-term damage even as the forbearance shown by survivors of Japan's quake-tsunami has been lauded in the West.
Commentators have heaped praise on the emotional resilience of people who have lost everything, but, say some, the surface calm masks deep undercurrents of emotion.
"To be honest I really feel like breaking down and crying -- because I'm sad," said evacuee Kenichi Endo, 45, briefly screwing his eyes shut.
"I've lost my father, my pet, my car, my savings. I've lost everything. But, everyone here is the same. If I cry, everyone else will, so I can't," he told AFP in a shelter in Onagawa town, clenching his fists into tight balls.
Unbearable tragedy was heaped on Japan on March 11 when a 9.0 magnitude quake unleashed a gigantic wave on the country's northeast, killing more than 13,500 people and leaving over 14,000 missing.
More than five weeks on and tens of thousands of evacuees are still living in school gymnasiums and other public buildings, sharing their sleeping space with dozens -- sometimes hundreds -- of other people.
Under these conditions, emotion remains tightly regulated.
Instead, grief appears at unexpected times -- while sleeping, listening to music or even while eating.
"The one thing I really want now is privacy," said Ken Hiraaki, an evacuee in another shelter. "At night I hear people groaning in their dreams. But sometimes my wife wakes me up because I am groaning too."
The unwillingness of many survivors to openly discuss their sadness is worrying health professionals, who say it makes them vulnerable to depression and long-term problems.
"Many people now are in a phase of acute stress disorder, which is a totally natural response to this level of trauma," said Ritsuko Nishimae, a clinical psychologist working with international aid group Doctors Without Borders (MSF) in Minamisanriku.
"If they are not able to get proper support psychologically, there is an increased possibility that they could develop post-traumatic stress disorder," she said.
In Japan depression continues to carry a stigma it has long shed in much of the West. This is especially marked in rural areas such as the disaster-struck northeast, where community and family ties are strong.
It is only in the past decade that metropolitan Japan has begun to tackle taboos on mental illness, with around 900,000 people a year treated for depression, a condition referred to euphemistically as "heart flu."
Psychiatrists, who are known as "heart carers", say many more people could benefit from treatment.
"When you say psychiatry, people become extremely sensitive. They think it is embarrassing," said Naoki Hayashi, a psychiatrist from Tokyo working in an evacuation centre in Rikuzentakata.
"They look at me quizzically, as if they're saying, 'Who are you?' So instead of telling them I'm a psychiatrist I just tell them I am a doctor," he added.
"Survivors feel guilty if they talk about their hurt because everyone is suffering. They feel they can't just come out and talk about it and that's particularly strong in rural areas."
Japanese medical groups have sent 115 "heart carers" to the disaster zone, but only 25 are doctors, with the rest being nurses and other medical staff.
At the evacuation centre in Onagawa there was little to indicate the "heart caring room" was anything out of the ordinary, its tatami mats and low table making it look like an ordinary dining room.
The centre's residents were all aware that it was there, but, despite the attempts of professionals to make the room non-threatening, few had ventured in to seek help.
"Japanese people don't like talking about themselves and their problems to strangers. I'd rather talk to my friends or family," said Keiko Katsumata, 57.
Survivors of World War II are usually even less open to the idea.
"Even if I do see a doctor like that, he won't solve my problems. I've experienced war, I've gone through a lot. That's where my strength comes from," said 77-year-old Toshiko Sawamura.
"We, the older generation, are different from the younger generation. They are weaker."