Differences between the novel and the film?

Old post, but I will answer anyway. At least two differences: Katsumi was pregnant, She was out and came home finding Joe Kelly dead, then she kills herself. Another was the way it ended very differently from the film. Don't know if you want to know the ending: so: Hana-Ogi does not leave with Gruver. She is unilke Katsumi, proud of being Japanese, she does not want to go go America. She loves her dancing career, and looks to her future in old age as the respected dance teacher of the Takarazuka troupe. She loves Gruver, but in their present, storing up the memories for when she ls old. Hana-Ogi leaves for Tokyo, leaving behind a handwritten message that she is going to Tokyo and that he should go back to America. Gruver grieves her loss and that of Kelly and Katsumi, but recognizes that he can no longer defy his superiors, without the reason that he had done so, recognizing that the army is his future

SPOILERS (if you intend to read the novel):

In the novel, Nakamura, the kabuki actor (Ricardo Montalban) does not exist. Joe Kelly is only nineteen years old. The relationship between Gruver and Hana-Ogi is much more developed. Joe shoots himself in the head, after which Katsumi stabs herself through the neck with a knife. In the end, Gruver and Hana-Ogi do not decide to risk everything for love and drive off together. The last time he sees her is from a distance on the street. They never get to say Sayonara face-to-face. Under relentless pressure from her theater handlers and his Air Force superiors, she leaves for Tokyo and he goes back to the U.S. and a promotion in rank.

The novel's end is harsh and heartbreaking. I find it hard to accept that Gruver would have given up without more of an attempt to at least see Hana-Ogi, discuss things, and properly say goodbye, if it came to that. But he just accepts the note she wrote to him under duress, and walks away forever. Not me! But I'm not Gruver.