Who is Angelica from On a Pale Horse and what is their importance?

Angelica's magic carpet is in front of Zane's when it falters and begins to fall. In the normal course of events, Zane would have saved Angelica, and the two would have fallen in love. Instead, Zane has sold his chance at happiness to the stone seller for a worthless wealthstone. The stone seller saves Angelica and earns her gratitude. Zane is depressed at missing his chance at the beautiful and apparently wealthy Angelica, and in his imagination, he imbues Angelica with all good qualities.