Self-harm blogs shelter in a dark, desperate corner of the Internet that few of us will ever see. But 14-year-old Anouschka, a baby-faced blogger, has lived here for months, collecting photos of slashed wrists and razor blades, reading grim, adolescent poems about death and loneliness — and meeting the first community of friends that she has ever really had.

Self-harm blogs are little understood outside the largely female, teen community that reads and writes them. To others, they can be disturbing: sites dedicated solely to cutting, suicide or eating disorders, replete with stomach-turning details, high-contrast photos and song lyrics from depressive teen bands. While self-harm content has been banned on Tumblr, one of the most popular blog platforms, since February 2012, almost 200,000 bloggers still use language related to eating disorders and self-injury, according to SimilarWeb, an analytics firm that tracks aggregate Web data.

That makes the blogs a serious public-health crisis. Or a profound resource for lonely, isolated teens — depending on whom you ask.