In print format , the eye would skim over the complete addresses, zip codes, dates, and time stamps.The choice not to edit these in the audio version, to only information as needed, creates a choppy Rhythm, which I found distracting and annoying. Otherwise, the epistolary structure is effective in casting a broad spectrum of interconnected relationships. Sibyl is a well crafted, imperious, self-righteous, self pitying, self centered soul who is very true to life, and.. unlikeable.
Spoiler alert: the sudden transformations in the final letters concerning finding her family, two suitors, a love affair, a new interest I travel, reconciliation with her estranged daughter, and oh yes, freeing herself from decades of guilt, seemed to me to erase all the complexities which make her an interesting character.