Beatrice Sparks – Treacherous Love: The Diary of an Anonymous Teenager (Anonymous Diaries)

Jennie’s father has walked out, and her mother seeks solace in pills. Her best friend abandons her to be with her boyfriend. Now her only friend is her diary, until she meets Mr Johnstone the substitute math teacher. Soon their friendship moves far beyond the classroom. Will her diary offer her a way to escape from this treacherous love?