DALLAS (CBSDFW.COM) — Patrick Zamarripa was one of the five officers killed in the ambush attack in downtown Dallas July 2016, and with every passing anniversary his father reflects on his heroic legacy while visiting his grave.

Rick Zamarripa said he visits his son at the DFW National Cemetery every chance he gets, but it doesn’t take away the pain he lives with everyday.

He was a husband, a father, a veteran and a “huge Texas Rangers fan.”

Patrick was working on July 7, protecting hundreds of marchers peacefully protesting police brutality when he was killed by a lone gunman.

Now — three years later — Dallas stops to honor these officers who lost their lives that night. But for Rick, he stops at his son’s gravesite because for him, nothing is the same.

“Every holiday — Thanksgiving, Christmas — Patrick used to walk in the front door and say, ‘Hey dad.’ Especially my birthday… It’s not the same anymore,” he said. “All these memories — they’re coming back of what happened.”

He said the ambush anniversaries never get any easier.

“I feel the same way I did the night of, and the night of was pretty hard,” Rick said. “A police officer’s life is just as important as your life and my life… They protect us.”

The Dallas Police Department plans to unveil a memorial sculpture designed by Dallas sculptor Barvo Walker this week.