Adult Children of Alcoholics by Janet Woititz. A brief, easy-to-read overview.
Some very insightful ways of looking at personal styles for dealing with emotional challenges, e.g., obsessive or narcissistic. If you realize what your primary and secondary character styles are, you become much more able to deal with emotional challenges well.
Body-Centered Psychotherapy, by Ron Kurtz...the chapter on character styles. Out of print, but often available on Amazon.com.
Character Styles, by Stephen Johnson--extremely hard to read on focused on problems rather than solutions, but also extraordinarily insightful. Johnson also has some more specific books, such as Humanizing The Narcissistic Style.
Feeling Good and the Feeling Good Handbook, by David Burns. Though the first book is repetitive, it has a lot of good content. The list of distortions in thinking is quite good. Some folks like the handbook (workbook) even more because you can DO it actively.
Poetry(a wild card)
The Year Of Lovemaking And Crying, by Kenneth Robinson. Bold, alive, irreverent, insightful.
The Essential Rumi. 13th-century Sufi mystic's poems still resonate for many of us.
The Dance of Intimacy (and the Dance Of: Anger / Deception / Connection / Fear) by Harriet Lerner. Well-written and insightful. Good theory, good examples. The Dance of Intimacy is easily one of my favorite self-help books. It has some good insight about the difficult task of staying focused on what you can change about a relationship rather than focusing on what you chronically wish the other person would change. These books are billed as being for women, but they have a lot to offer any reader who's human.
Your Perfect Right. A classic on assertiveness.
He's Just Not That Into You. Helps you get out of the classic trap of interpreting mixed messages as meaning "I'm wild about you; it's just that...." Helps you realize that the mixed message sender simply isn't on board...and probably won't be any time soon.
The Courage To Heal and The Courage To Heal Workbook. Though it has a particular focus on women and incest, it's helped many men and many people whose sexual violations weren't from family members. A great resource.
Victims No Longer. Specifically geared toward male survivors of sexual abuse.
For people who find therapy fascinating, Irwin Yalom's non-fictional books are amazing.
Every Day Gets A Little Closer: A Twice-Told Therapy. Yalom and his client both tell the story of their therapy. It's amazing to see where their experiences overlap and (especially) where they don't.
Love's Executioner And Other Tales Of Psychotherapy. Yalom tells the stories of ten cases of psychotherapy.