Not quite sure what to make of the ending

Rating: 7/10 (15 February 2017)

This movie was an intense thriller but left me hanging with unanswered questions. I think 7/10 is a fair review since, as other people commented, James McAvoy was excellent. But the story was a bit slow at the beginning, with unnecessary scenes and plot holes. For instance how did "Kevin" or one of his personalities manage to email the doctor when apparently there wasn't internet service in the basement. Secondly, why didn't the Doctor contact police and why did she go alone to Kevin's hideout? As for the ending, I'm still not sure what to make of it. It didn't deliver the big TWIST like I was expecting. I agree with others, it lacked closure. I was really hoping for better; like that Casey didn't have to go back to her abusive Uncle and Kevin was caught.