One Friday afternoon five years ago, Nelba Márquez-Greene sent two of her children to school in Newtown, Connecticut. She only got one back.

As a marriage and family therapist, she's well-versed in the language of trauma and grief. But her fluency has become a lot more personal since her 6-year-old daughter Ana was murdered in the Sandy Hook Elementary shooting.

Márquez-Greene now apportions her energy thoughtfully. She knows this month, more than the others, she needs extra space to grieve, work, and be a mother and wife — not that her emotional and personal responsibilities can be easily separated. She's the founder and director of the Ana Grace Project, founded in the memory of her daughter, that works to address social isolation and social justice in schools.

Márquez-Greene mourns the loss of her daughter, but she also mourns the version of herself that existed before the shooting; a woman with a naive but steadfast belief that she lived in a place where a mass display of gun violence could never happen.

“I would say that the only difference between the early days and now is that the shock has worn off,” Márquez-Greene said. “When you have lost a child, a beloved, prayed-for child, to gun violence, I will only say for us, it doesn't get better.”