In a posting on her Twitter page before the shooting, she wrote: "I live a good life....a hard one, but I go to sleep peacefully @ night knowing that I may have made a difference in someone's life."
Munley's brother Daniel Barbour told ABC News that his sister had been shot three times in the hand and the leg.
One of the bullets pierced an artery, requiring her to undergo surgery Friday.
The diminutive Munley - she stands 5-foot-4 and weighs about 120 pounds - served as a cop in Wrightsville Beach,
N.C., before she moved to Texas to enlist in the military, friends said.
She is married with two daughters and is no longer in the armed forces.
"She's the happiest, sweetest, most fun-loving girl you'd ever want to be friends with - and never want to cross," Peterson said.