The book of unknown Americans

The symbolism of the novel's ending is this: the mysterious effects of Maribel's injury are reversed upon her mother's decision to immigrate back to Mexico, as if to suggest that it were some kind of spiritually attachment to their homeland which would heal life's most pressing problems. Maribel's restrictions are symbols for those "pressing" problems, because the pressure of her injury makes her life radically different and also quite difficult in comparison to normal time. The reversal is a cyclical symbol for healing.