The ending
All along her therapist was a sexual predator. Her last story about being beat up and then peed on was what finally turned him on. He waited until she was asleep to creep into that bed and have his way with her.
I knew that he was BSing about his asexuality and deserved to die.
I bet that she used her sexuality to get him to reveal his true nature just like she did with the pedophile earlier in the movie.