Horse Tamer's Fiery Lady — Susan Kelley

Sassy, intelligent Dr. Madden Lake uses rugged horse trainer, Forrest Gibbs, in all the ways she must to save humanity and herself.

Humanity teeters on the brink of extinction three hundred years after a plague destroys modern civilization.
Forrest Gibbs, a talented horse trainer, survives on the wild frontier with his siblings and others immune to the lethal disease. But his people are too few, causing a dangerous lack of genetic diversity in their gene pool. The only solution is to save the inhabitants of a city protected by a sterile bubble.
Dr. Madden Lake has spent her entire life looking for a cure to plague as the city's resources dwindle. Then her world and beliefs are spun around when a rugged frontiersman kidnaps her. More shocking than the discovery that people live outside the bubble is that those same primitive people have the cure.
Forrest babysits the hot-tempered, snippy doctor as he escorts her to his home. Her verbal barbs create a friction between them that grows into a different kind of heat. Madden has never met a man like Forrest. He moves in complete harmony with the savage outside world and isn't a bit intimidated by her sassy manner or intelligence. She's not sure who seduces whom, but everything between them is a perfect fit. Except the future. Forrest can't accept that she must return to the city to bring the cure to those suffering within the bubble.
Forrest and Madden hold the future of mankind in their hands as they battle the weather, outlaws, and their differing opinions on saving the city. Forrest must decide if the life of the woman he loves is more important than the lives of thousands.