She's Come Undone by Wally Lamb

Meet Dolores Price. She's thirteen, wise-mouthed but wounded, having bid her childhood goodbye. Beached like a whale in front of her bedroom TV, she spends the next few years nourishing herself with the Mallomars, potato chips, and Pepsi her anxious mother supplies. When she finally rolls into young womanhood at 257 pounds, Dolores is no stronger and life is no kinder. But this time she's determined to rise to the occasion and give herself one more chance before really going belly up.

In this extraordinary coming-of-age odyssey, Wally Lamb invites us to hitch a wild ride on a journey of love, pain, and renewal with the most heartbreakingly comical heroine to come along in years. At once a fragile girl and a hard-edged cynic, so tough to love yet so inimitably lovable, Dolores is as poignantly real as our own imperfections.

Paperback, 1992

Goodreads: 3.91