I described this on a friend's Friday Reads Facebook discussion as "an Eleanor and Park readalike, but more suicidal." That's probably all you need to know if you like Rainbow Rowell and mental illness novels. It's a great read, but...heavy.
It's told in two voices, that of Theodore Finch, who may have undiagnosed bipolar disorder, and Violet Markey, whose grief over her sister's death has put her life on hold. The two meet in an Indiana public high school bell tower. They more or less save each other at first sight, but it takes a while for them to fall in love.
Finch is a smarty and well-versed in suicide lore. This tidbit intrigued me:
A Chinese man died from lack of sleep when he stayed awake for eleven days straight as he attempted to watch every game in the European Championship (that's soccer for those, like me, who have no clue).
You can die from lack of sleep? It makes sense, I guess, but still seems surprising.
I was moved by one of the character's late-in-the-novel revelations that "it's not what you take, it's what you leave."