Planet Janet In Orbit by Dyan Sheldon

Having taken a break from the 'Dark Phase' of her life, Janet records in her diary the trials and tribulations that occur as she finds a summer job, witnesses the changes in her mother and best friend as they fall in love, and approaches her own seventeenth birthday.

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Exams are over, love is in the air, and Janet's summer is already down the pan. Not only has her mother (The Mad Cow) got a new, right-on boyfriend with two daughters from hell, but she is expecting Janet to get a summer job! Add to that a lovesick dad, a best friend going gooey over a gorgeous Australian and a suffering, pregnant, lesbian aunt - and you have enough to send anyone into orbit. Welcome to Janet's Planet...