LOS ANGELES - Caila Sanford rushed to donate blood as she wiped tears from her eyes. She started reliving a nightmare after hearing about the mass shooting at the Borderline Bar and Grill in Thousand Oaks, Calif.
Sanford, 22, survived the mass shooting at a concert in Las Vegas just a year ago, where a gunman killed 58 people.
"This really hits home for me. I can imagine what these people are going through. I've been to this bar many, many times. I love college nights," Sanders said.
It was college night at the Borderline when a gunman entered and opened fire, killing 12 people and then himself.
The shooter was identified as Ian David Long, 28, a former military machine gunner. He apparently killed himself after Wednesday’s attack.
It was the second U.S. mass shooting to make recent headlines. An attack Oct. 27 at a Pittsburgh synagogue killed 11 people.
Researchers at the Gun Violence Archive said there has been a mass shooting in the United States nearly every day this year. The group defines a mass shooting as an incident in which four or more people are wounded or killed by gunfire, not including the shooter.
The frequency of mass shootings leaves some Americans numb.
"It doesn't get easier to hear, but it gets more normalized. It's desensitized completely," Sanford said, adding, "I think twice about going anywhere, honestly. Not just here — the grocery store, the mall."
Parents worry that not even schools are safe. In May, a mass shooting at a school in Santa Fe, Texas, left 10 dead.
"We are living in a state of fear within our own country, within our own borders, amongst ourselves," said Grace Fisher, a mother of three young children.
Fisher went to the scene of the most recent shooting in Thousand Oaks with a sign that said, "Moms demand action for gun sense in America."
She said U.S. society must find better ways to prevent such carnage.
"I think that the problem in this country is multifaceted. It's going to take a multifaceted approach to solve this problem, but to say that guns are not the problem is a total cop-out," Fisher said.
In addition to worrying about a test in school, students also have to think about an exit plan if they experience an active-shooter situation.
"Parents and teachers now have to have these conversations with kids who are in school. ‘What are you going to do if this happens? What is your plan? Where are you going to go?’ And they shouldn't have to worry about that," Sanford said.