This book is about Christians who are single by choice, as a calling. To the author, I think, singles are not just people in a certain demographic box, but they're almost their own personality type. They are altruistic, introverted, individualistic, thoughtful, aesthetic and generous. Perhaps she was generalizing from herself, but for me, someone living this lifestyle and drawn to this vocation, I see myself as being basically exactly the same, and so perhaps there's something to the notion.
In one sense, I found this book refreshing and interesting, in that it came from a perspective that I feel has been left out of a lot of the evangelical Protestantism I'm used to. I'm not sure exactly how to express it. On the other hand, many of the chapters were hard to read because the language was abstract. Maybe a typical evangelical Protestant book would have avoided that kind of abstraction. If you begin this book and find yourself wanting to give up out of a sense that the book is a burden on your attention, skip to chapters 6, 7, and 8 which are a relief. Chapter 5 isn't too bad either. Of course, some readers (perhaps those who are single as a vocation) are readers by vocation, and should read even the burdensome parts, as a desert experience.
The bibliographies, one per each chapter, contain brief "human readable" summaries of each book. This is a good thing for non-fiction books to do.
Things I learned, or hadn't considered before:
Singles get to give more of their life socially, so they also need to spend more time in solitude than other people.
Singles tend to be looked on by other people as the people to do extra work because they don't have "good excuses" to be at home (i.e. families). Solitude is devalued, considered a self-indulgent luxury.
Therefore singles tend to wind up working too hard in order to overcompensate for this perception of self-indulgence.
Singles develop refined tastes and heightened understanding (because of their solitude) which must be fed, and protected from people who don't understand. Non-singles have a tendency to try to level singles.
Everyone is single, everyone has an individual life. We all are born single and die single. Vocationally single people understand the uniqueness of people more of the time.