The Art Of Happiness by Dali Lama - I'm not religious or Buddist, but this is a good book!
This book could change your life. It did for me with the simple suggestion of a way to see what is most important in life.

The 7 Habits by Stephen R. Covey - This book is about getting yourself in a great mode of thinking. About how you view things and people. How you react to them, and how you set goals and really go after them. How does that relate to love? Read my highlights from reading the book below... then buy the book! Really worth it. I've read this book and worked through the self-examination parts, it is helpful. AWESOME BOOK!!

Are you the one for me? by Barbara DeAngelis, Ph.D. - There are many selt-tests in this book that help you determine things about yourself and whom you want to be with, plus some good advice and points. Good to get the book just for the tests.