Rest Stop (2006) on Netflix

Plot summary

Nicole Carrow is an aspiring actress who leaves Texas with her boyfriend Jess Hilts to head for Los Angeles. On an old road she asks him to pull into a rest stop. When she comes back out, Jess is gone. The man in the old yellow truck throws her the cell phone left in the convertible, and she understands he has taken Jess. She asks an RV for help and the passengers throw her out after she sees a deformed person hidden in the back. Back at the restroom she finds a girl covered in cuts hiding in the maintenance room, who warns her about the killer who tortured her.