In addition to the above, here are some that have helped me:
Beyond Codependency: And Getting Better All the Time, by Melody Beattie (I found this one even more helpful than the first, but the first lays important groundwork)
Setting Boundaries with Your Adult Children: Six Steps to Hope and Healing for Struggling Parents by Allison Bottke
Stop Walking on Eggshells: Taking Your Life Back When Someone You Care About Has Borderline Personality Disorder, by Paul Mason and Randi Kreger
The Essential Family Guide to Borderline Personality Disorder: New Tools and Techniques to Stop Walking on Eggshells, by Randi Kreger (again, I found this one even better than the first volume because it gave specific suggestions, but again the first lays impt. groundwork).
Full Catastrophe Living: Using the Wisdom of Your Body and Mind to Face Stress, Pain, and Illness, by Jon Kabat-Zinn (teaches meditation techniques)