All of the characters (except for the police officers and the head of the covenant) are lied to about who the protagonist is and what her life has been like, as the movie is about her being in witness protection.
No one has an eating disorder, though at her first meal at the covenant, the protagonist refuses to eat a meal she doesn't like, and she is forced to skip supper as a result.
At the end of the movie, a bad guy gets shot in the arm. It's not excessive but they clearly show a wound. There is also gunplay before this scene, and there is a round of gunplay in the first 20 minutes of the movie as well.