KELLIE PICKLER brought a handsome date to Wednesday's CMT Awards . . . but he wasn't her husband, Kyle Jacobs.  His name is Sgt. Sean DeBevoise, and he's a Marine who was wounded in Iraq back in 2006. 

Kellie Tweeted a picture of them at the show on Wednesday . . . and wrote, quote, "Me and my date."

Kellie met Sgt. DeBevoise at a charity event in North Carolina, and he invited her to the Hope For Our Heroes, Got Heart, Give Hope Gala, which went down last month in Washington D.C.  Kellie couldn't make it so she invited him to the CMT Awards.

Sgt. DeBevoise story is pretty compelling.  He was wounded in combat several times . . . and at one point was told he'd never walk again.  He proved everybody wrong.