Sorrow's Knot, by Erin Bow
I have yet to meet an Erin Bow novel that isn't really well done. This one is set in an imagined fantasy world that is clearly based on the native cultures of Northwest America, in contrast to Bow's first novel with a fantasy Slavic setting.
Otter lives in a tiny village at the very end of the human world, where her talent of binding is all-important and keeps everyone safe -- for the dead are always at the edges, trying to get in. Together with her two best friends, Kestrel and Cricket, she works and prepares for adulthood, when she assumes she'll become a binder like her mother, tying special knots to ward off danger. (It sounds exactly like cat's-cradle.) But then her mother goes mad and rejects Otter as the next binder, and there is something wrong with the knots. Otter, Kestrel, and Cricket have to leave the safety of the village to find their own people's history and learn what went wrong.
Eh, that's not a very good summary, but Sorrow's Knot is very good, pretty tragic, and altogether a worthy YA read.