Devil In The Flesh / Dearly Devoted [1998, USA, thriller, DVDRip]

Debbie Strand set a fire that killed her mother and her mother's boyfriend, and is sent to live with her elderly grandmother, who is an ultra-conservative fundamentalist Christian and her dog. Her grandmother is abusive and physically violent, and even forces her to wear her demeaning, outdated clothes. Debbie kills her grandmother's dog and beats her grandmother to death with her cane after she reads her diary and tells her she's putting her in a reform school. Debbie also eyes one of her new teachers, Mr. Rinaldi. After learning that he has a girlfriend, she deletes her messages on his answering machine and tries to kill her so she can have Mr. Rinaldi to herself. Debbie is eventually arrested and placed in an institution.