17 & Gone, by Nova Ren Suma

Seventeen year-old Lauren sees missing girls.  Girls who ran away, girls who stepped out for a minute, girls who got into the wrong car.  All of them seventeen like her and now gone.  It started when she found an old missing person flyer, but quickly became an obsession as she hunts down more examples and finds out how many of them there are.  How easy it is to become "gone" where you're young and female.  

The girls talk to her, telling her their stories and how to find them.  They tell her the things they wish they could tell their families.  Lauren has become a conduit for them. And in doing so, she loses touch with herself.

A graceful story of a descent into schizophrenia -- a common enough trope in YA.  What makes this one stand out is its theme:  the danger of being female and seventeen.  A lot of seventeen year-old women  disappear. They are hard to find and frequently disappear under circumstances that leave them abandoned and forgotten.  A young woman runs away from home.  Does she disappear because she doesn't want to be found or because she has been abducted?  Or perhaps initially the first and then the latter?  And for those safe at home, how easy is it to become overwhelmed by all the dangers that are out there?  All of the reasons and ways in which a girl can become gone?  And how seemingly little concern there is that so many of them are missing?  The novel, as compelling as it is in its storytelling, is equally unsettling in its message.