Although it’s been 22 years since the deadliest terrorist attack in human history, many Americans may again re-experience painful memories of losing their loved ones on September 11.

"With the anniversary of 9/11 right around the corner, many people are struggling with traumatic memories of the terrorist attack that shook the nation and changed the entire world," Dr. Lama Bazzi, a psychiatrist in private practice in New York City, told Fox News Digital. 

"Anniversaries of tragic events can serve as triggers for grief," he said, "that the individual thought was long resolved."

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Fox News Digital spoke to experts on how to cope if you find yourself triggered by grief on September 11.

Here are insights and suggestions.

In 1969, American psychiatrist Elizabeth Kübler-Ross described in her book "On Death and Dying" what is now widely popularized as the five stages of grief: denial, anger, bargaining, depression and acceptance.

It was based on the experiences of people who were near the end of their lives — but it's expanded to apply to many other types of loss that engender grief.

Some modern experts are critical of the Kübler-Ross model of grief, since many people’s journeys may not follow a "textbook" timeline of emotions.

"What is undeniable is that the first ‘stage’ or ‘state’ of grief is shock and disbelief, and the final ‘stage’ or ‘state’ of grief is adjustment (reintegration)," Dr. Holly G. Prigerson, co-director of the Center for Research on End-of-Life Care at Weill Cornell Medicine in New York City, told Fox News Digital via email.

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"Folks can quibble about the intermediary stages or states, but we found in the Yale Bereavement Study evidence supportive of what Kubler-Ross proposed."

She added, "That is not to say that some mourners do not get stuck."

People who "get stuck" may be at risk of prolonged grief disorder (PGD). 

"PGD is a significant health condition that poses risk of adverse outcomes, including dying of a broken heart (e.g., Takotsubo syndrome)," Prigerson wrote in an email. 

Broken-heart syndrome, also known as stress cardiomyopathy or takotsubo syndrome, can occur when a person experiences severe emotional or physical stress, according to Harvard Health Publishing. 

"Our preliminary results," added Prigerson, "point to social connections with ‘simpatico’ others that address those social gaps and fill the voids created by the loss of a loved one."

Friends and family help these patients the most with "interventions that fill the social gaps, or deprivations, that follow from their special type of loss," she also said.

Denial is the first stage that "numbs" us to give us time to process what just happened.

As the news sets in, it’s common to wear a mask of anger to hide the pain we are not ready to feel.

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In the third stage, we often start bargaining, usually with "if only" scenarios — hoping that if we turned back time, things would have worked out differently.

Depression then eventually seeps in.

Yet over time, most people come to accept the loss as their new reality.

Still, some experts say the model, however useful, may not always apply to all circumstances of grief, such as the great tragedy of 9/11.

"It is important to move away from the concept of five stages of grief when conceptualizing the traumatic effect of a public and catastrophic event like 9/11 resulting in a personal loss," said Bazzi of New York City. 

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"Grief does not depart," she said. 

"Rather, it becomes a part of the person's fabric and becomes integrated into the way they see and experience the world." 

As an anniversary approaches, grief can be overwhelming because it comes on suddenly and can be unexpected, Bazzi said.

The only way to deal with the grief is to have the courage to muster through it with the expectation that it may resurface again, she suggested.

"It is important for individuals who suffered personal losses in 9/11 to avoid isolating themselves and to lean into their communities and support systems," Bazzi said.

"Grief connects us with all of humanity," Dr. Martin Rubin, psychiatrist and course director of a popular wellness elective for medical students in Elk Grove, California, told Fox News Digital.

Realizing this, Rubin said, helps people heal. 

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Bazzi recommended limiting exposure to "news cycles that will repeatedly show images of the attack and lead to unnecessary hyperarousal and activation."

"Engaging in healthy activities that take people out of their heads and put them in their bodies, like hiking, yoga, biking or other vigorous activities is very therapeutic."

When people experience an immense loss, she also notes the uncomfortable truth that grief becomes intertwined in the fabric of our lives.

If people can become comfortable living with grief rather than expecting to get over it, "grief can become less daunting and a way to honor a loved one's memory," Bazzi said.