I do not do this myself, but my mother used to scratch her hand until it would bleed. She stopped doing this after she got treatment for her anxiety / panic disorder. Have you tried looking up info on trichotillomania? This is the term for obsessive hair-pulling, and it applies to eyelashes. Trichotillomania is usually associated with anxiety, but some people also view it as a form of self-mutilation (like cutting). Is there anyone you can talk to about this (family member, school counselor, your doctor, etc)?