Her Cheyenne Warrior

This is an Apple Books audiobook narrated by a digital voice based on a human narrator.
The Cheyenne's captive! 

Runaway heiress Lorna Bradford must reach California to claim her fortune, but when she's rescued from robbers by fierce warrior Black Horse, she's forced to remain under his protection. 

Immersed in a world so different from her own, wildcat Lorna learns how to be the kind of strong woman Black Horse needs. But, to stay by his side, she must first let go of everything she knows and decide to seize this chance for happiness with her Cheyenne warrior!