"Were she better or you sicker, then the stars would not be so terribly crossed, but it is the nature of stars to cross, and never was Shakespeare more wrong than when he had Cassius note, "The fault, dear Brutus, is not in our stars/ But in ourselves." Easy enough to say when you're a Roman nobleman (or Shakespeare!), but there is no shortage of fault to be found amid our stars."
The quote that named the book:
Peter Van Houten, The Fault in Our Stars by John Green