Rebel: Thief Who Stole the People might work (ML's first love is alive and he's in love with/married to the FL but all his interactions with his first love felt like there was some lingering feelings, at least to me).
Maybe Faith (ML's fiancée is dead and he clearly loves the FL by that point of the story, but still basically tries to commit suicide to both protect the FL and to reunite with his first love before he "forgets what she looks like).
Also, possibly The Forbidden Marriage (ML seemed a bit conflicted to me and both in love with the FL and still in love with his dead wife).