Inside Intentional Self-Injury
A Nursing 2011 article discusses methods for identifying signs of self-injurious behavior (SIB), and ways to intervene effectively.
"Although people may engage in SIB [self-injurious behavior] for any combination of reasons, the primary one is to cope with their emotions and to feel better. These emotions may occur individually or in combination, or one may follow another. The emotion may be different from episode to episode."