NASHVILLE, Ind. -- A U.S. Marine sergeant from Indiana was killed Thursday in Afghanistan, the Department of Defense said Saturday.

Sgt. Jeremy R. McQueary, 27, of Nashville, died "while supporting combat operations in Helmand province," the DOD said.

McQueary was assigned to the 2nd Combat Engineer Battalion, 2nd Marine Division II Marine Expeditionary Force and was based in Camp Lejeune, N.C.

McQueary was on his third deployment overseas and was supposed to return home in two months. The previous two tours had been in Iraq.

Rae McQueary told 6News' Sarah Cornell that her husband was killed when a bomb hit him as he stood next to his vehicle.

Stricken with grief, Rae doesn't remember what was said when another Marine came to her door Thursday to tell her of Jeremy's death.

"It's just unbelievable. I mean, it can't be," she said. "It's still kind of hard to believe that it's him. I have not seen a body. … In my heart, I just want to believe that it's not real."

Originally from Columbus, McQueary and his wife had moved to Nashville, where they lived when not at the base in North Carolina.

Rae last saw Jeremy when he was given leave from his deployment to Afghanistan -- home for six weeks to see the birth of their son.

"Hadley doesn't know what he lost yet, but he lost the best person he'll ever know," she said. "Somehow for Jeremy, I'll show him that."

As a surprise for her husband, Rae had recently gotten a tattoo with initials for their names and numbers for their wedding date, though the number 18 is now symbolic of something else -- the day her husband lost his life fighting for our country.

"I know that whether you agree with the war or not, he was fighting for our family, for your family," she said.