Stepping Heavenward by Elizabeth Prentiss

Project Gutenberg
Written in the form of the protagonist's journal, Stepping Heavenward chronicles one woman's sometimes tempestuous, sometimes joyful journey from girlhood on through marriage and motherhood, and her struggles and successes with faith and family life.

Fräulein Schmidt and Mr. Anstruther by Elizabeth von Arnim

Amazon | Project Gutenberg
A delightful little book, told entirely through the sprightly letters of a German girl to a young Englishman. Though their relationship to each other undergoes changes during the course of the book, Rose-Marie's perceptive, often humorous and sometimes bittersweet chronicling of the ups and downs of her life is the book's center and its chief charm.