Your interpretation is correct. This final passage from John Buchan’s The Half-Hearted depicts the heroic, solitary death of Lewis Haystoun on the Indian frontier.
While the previous chapters built up the “Bridge of Broken Hearts”—the emotional tie between Lewis and Alice—this conclusion solidifies the “austere love” they spoke of. Lewis does not return to her; instead, he sacrifices his life to hold a mountain pass against an invading force, alerting the British Empire to the threat and effectively stopping a secret Russian-backed plot.
The Significance of His Death
The passage highlights several key themes that define the end of the novel:
* Redemption through Action: Throughout the book, Lewis is portrayed as “half-hearted”—a man of great potential who lacks the “will to power” or the ability to commit fully to a cause or a woman. His death is his final act of becoming “whole-hearted.” He moves from being a “phrasing fool” (as Marka calls him) to a man of decisive, world-altering action.
* The Contrast of Perspectives: The three different reactions to his body emphasize his transformation:
   * Marka (The Villain): Sees only a “fool” who ruined a career’s worth of political maneuvering.
   * The Narrator: Notes the “broken gold signet-ring,” a lingering symbol of his aristocratic, “civilized” past that has been literally trodden into the dirt.
   * Fazir Khan (The Warrior): Initially kicks the body in frustration, but ultimately recognizes Lewis’s spirit. His final tribute—”This man was of the race of kings”—elevates Lewis from a failed politician/lover to a mythic hero.
The Fate of Alice
As you noted, there is no reunion. The “high stone tower” Alice mentioned becomes her reality. She is left with the “illumination which only sorrows and parting can bring.” By dying, Lewis remains “the knight at the World’s End” who never forgets, preserving their love in a state of tragic perfection rather than let it face the complications of her previous engagement or the “modern note” of their social world.