When photos and videos began appearing on Monday, we watched as news of the burning Notre Dame Cathedral captivated us in horror.

CNN's Brian Stelter described a universal state of shock: "United in helplessness. Unsure of what to say. But compelled to watch."

Tourists and journalists first shared images of the fire via their camera phones, and they spread quickly through social media. Regular people soon joined in.

Some posted photos of themselves in front of the cathedral. Others sent prayers to "Our Lady." Some just said they were feeling helpless, like a person — not a building — had died. And they couldn't understand why they were so sad.

There are several reasons the building's tragedy may have hit us so hard, licensed therapist Edy Nathan tells MNN. Nathan is the author of "It's Grief: The Dance of Self-Discovery Through Trauma and Loss."

"There are certain places, whether it was the World Trade center or Notre Dame, that we believe are always going to be there. Especially with Notre Dame, it has survived so much," Nathan says.

"We as humans, somehow we live through it. To see it destroyed, it represents some of our own fragility. It’s not there for a minute, like we are, it’s there for eternity. It represents not only faith and god but a history that proceeded us and will go beyond."

Mourning across religious lines

Smoke rises around the altar in front of the cross inside the Notre Dame cathedral. Smoke rises around the altar in front of the cross inside Notre Dame Cathedral. (Photo: PHILIPPE WOJAZER/AFP/Getty Images)

The tragedy reached across many lines, having much more than religious significance. That the fire happened during Holy Week, the most sacred time in the Christian calendar because it marks the death and resurrection of Jesus, made it especially hard for Catholics, who reacted in horror and disbelief.

Notre Dame is probably second only to St. Peter's Basilica in Vatican City, Rome, as the most meaningful, iconic church to Catholics. The church is home to many important relics, including what is believed to be the crown of thorns placed on the head of Jesus during his crucifixion. (The crown and other relics were rescued from the fire, several outlets have reported.)

Many non-Christians also recognized the spiritual and historical significance of the blaze. Some 13 million people visit the cathedral each year with an average of more than 30,000 tourists per day. On some days, more than 50,000 pilgrims and visitors enter the cathedral, according to the Notre Dame website. It is the most-visited spot in Paris, as many come to see what is considered one of the finest examples of French Gothic architecture.

"The beauty spoke to us on so many universal levels," says Rabbi Benjamin Blech, a best-selling author and professor at Yeshiva University in New York. "It isn't just Catholics who are in mourning. All of us, every religion, appreciates this paean to the past. We mourn with Catholics today because something holy was lost."

It's proof that the past really resonates with us in a remarkable way, Blech says.

"Remembering the past makes us who we are. The fact that something so old and venerated and imbued with the sense of something spiritual burnt in a remarkable big way puts us in a situation where we can reflect on the past."

A sense of togetherness

Bystanders in Paris shared early images of the fire with people around the world. Bystanders in Paris shared early images of the fire with people around the world. (Photo: LUDOVIC MARIN/AFP/Getty Images)

We used to tackle our grief alone or with a few close friends or family members. But in the age of social media, we can instantly share our sadness with people all over the world.

"Social media can calm us. It can also make us realize that we embody more similarities than we know," Nathan says. "That we don’t have to be a devout Christian to feel the sorrow of the loss. You can be any religious person. It can be that you love art or history. You could hear the voice of the burning building and the grief around the world. So often we are isolated in our grief and this is when social media helped us feel not so alone."

In every tragedy, there's a seed of hope, Blech says.

"In the response, there was togetherness of people of all faiths," he says. "When a tragedy of this sort supersedes divisiveness and rises above the ways in which people of different religions worship, it brings us together. When something reminding us of our spirituality goes down in flames, our coming together is a positive message."

While the cathedral burned, strangers came together to sing "Ave Maria."

Not knowing how to help

This universal coming together also helps when there's uncertainty about what to do next.

Often when there's a tragedy like a natural disaster, we know to donate money or supplies. We may even offer to provide hands-on assistance. But in this case, there were no people injured or displaced from their homes. There's no need for food or shelter, so we may feel at a loss because we don't know how to help.

There's still the need for money, of course. French President Emmanuel Macron announced that France would launch a fundraising campaign to rebuild the cathedral. Two French businessmen immediately pledged millions of euros toward the reconstruction and several fundraising sites were immediately launched online. About 24 hours after the blaze had started, nearly 5 million euros ($5.6 million) had been raised on one site alone.

For many, the only thing to do was pray. It became a time for healing and perhaps a time for renewal.

"Maybe in this time of collective grief, it's a time that will allow people to reignite their own spirituality," Nathan says. "Perhaps it's a sense of renewing our own faith or maybe a time to speak to people we haven’t spoken to. In Paris, they're talking about rebuilding. How can we do that with our own lives?"

Mary Jo DiLonardo writes about everything from health to parenting — and anything that helps explain why her dog does what he does.

Grieving for Notre Dame Cathedral in the age of social media
As Notre Dame Cathedral burned, people expressed their sorrow on social media. A therapist walks through how grief (even for a building) is different now.