Title: Mary Marie
First published: 1920
Description: The story revolves around a young girl, during the early 20th century, trying to adjust to her parents' divorce and  joint custody--she spends half of each year with each parent, traveling between their cities of residence.  Her parents do not agree on any subject, including her mode of dress, her indulgences, her behavior, or even on what to call her; her father calls her Mary, her mother calls her Marie.  In her diary, Mary Marie decribes her feelings on everything affecting her life, including her preference for her mother's frivolous lifestyle and rejection of her staid father's rigid rules and dress code.  Unfortunately, from Mary Marie's point of view, her mother begins a discipline regime, explaining that it is for her own good.
Subjects: marriage, divorce, reconciliation, teenager, diary, happy ending, Fiction, general
Places: I believe she is shuttled back and forth between Boston and New York.  (It's been a number of years since I read the book.))
People: Mary Marie is the main character, with her parents and paternal aunt trying to shape her behavior.
Time periods: The descriptions sound like early 20th century or very late 19th.
LC classification: PZ3 .P366Mo