Again Again by E. Lockhart

If you could live your life again, what would you do differently?

After a near-fatal family catastrophe and an unexpected romantic upheaval, Adelaide Buchwald finds herself catapulted into a summer of wild possibility, during which she will fall in and out of love a thousand times--while finally confronting the secrets she keeps, her ideas about love, and the weird grandiosity of the human mind.

A raw, funny story that will surprise you over and over, Again Again gives us an indelible heroine grappling with the terrible and wonderful problem of loving other people.