"This tragedy is so deeply affecting the national psyche, reminding us of 9/11, because of its assault on Norman Rockwell's vision of America," psychiatrist Carole Lieberman tells PEOPLE.
Friday was proclaimed a national day of mourning for those lost a week ago, with a moment of silence called for at 9:30 a.m. Eastern time, as 26 churchbells rang in Newtown and elsewhere. In addition, First Lady Michelle Obama sent an open letter of condolence to the town, saying the entire nation "is holding you in our hearts."
But how do those directly involved with the tragedy find the strength to cope?
To do that, family members who lost loved ones need immediate counseling and to maintain their normal routines. They also need to draw support from other affected families who can relate to what they're going through, says Dr. Stephanie N. Marcy, a psychologist at Children's Hospital Los Angeles.
"I think the people on the ground are feeling a sense of hopelessness because there is no way to justify what happened," Marcy says. "They need to be around other people who have experienced and understand it. If you were all involved together, you can empathize and grieve together."
In many of these families, the remaining children might have survivor's guilt, she adds.
"They rethink what they did that day and wonder if they in some way contributed to the death of a sibling, or they wonder, why did I survive?" Marcy says.
Therapists will need to explain to kids who lost a sibling that their "false belief that they should have been able to prevent it is not correct," adds Marcy.
Children at Sandy Hook may also have Post-Traumatic Stress Disorder and will need therapy, Lieberman says.
What to Tell ChildrenAnd what do parents whose children were not involved in the tragedy tell their own youngsters about what happened? That, Marcy says, depends on how old they are and how much they know already.
"Kindergarteners and first graders don't need to be told about it unless you think they will hear it somewhere else. For older kids, you have to get to know what they know, answer any questions they might have, and be truthful – but don't say too much," Marcy says. "Say that a person who was having problems, that was sick, went into a school and injured some people for no particular reason. Tell them it would never happen at their school."
"Yes," she adds, "it could happen anywhere. But there's no point in letting your child think that, [because] they may be flooded with fear."
For the adults and children across the country who have been vicariously traumatized, Marcy says, "We need to regain our sense of control, because this type of event makes us feel completely helpless."
Lieberman adds that Americans "are also feeling a generalized anxiety, a fear that no place is safe anymore. They need to talk to friends and family, get involved in championing causes that make society better, to volunteer for charities, and to get psychotherapy if the sadness and anxiety persist."