He Saved Her Life, She Cast Him Out

When a young woman faces certain death, an immortal guardian agrees to save her using his own life force, sustaining her for three years at great personal cost. Believing his help means real love, she pursues him aggressively and forces a betrothal, but he discovers she only wanted him as a shield against someone else's affection. Just as he decides to quietly leave once she's fully healed, her family turns against him and casts him out, dismissing his warnings that ignoring their bond will bring disaster.