"I can't sleep. I can't eat. Just to think of her out there, it's horrible," said Lee Johnson, Anne-Christine's father.
Anne-Christine, a mother of two boys, was last seen by her ex-husband. Police have interviewed him twice.
Investigators are not calling him a suspect.
"Eleven days since her disappearance. We're very concerned," Kelly Williamson said.
Williamson, with the League City Police Department, said they have several investigators working the case. They have no evidence she left on her own, but cannot say they suspect foul play.
ORIGINAL REPORT: League City police searching for missing woman
Her disappearance remains a mystery.
"If she does not return, we're going to find out who's responsible for her disappearance and hold them accountable," Williamson said.
Anne-Christine's family wants her back home.
"I just want her to be found alive. Somewhere," her father said.