A Long Petal of the Sea by Isabelle Allende

The story starts in Spain in the 1930s as the Spanish Civil War is blazing away. Victor is a medic. His brother Guillem is a soldier. Roser had come to live with the family as a young child through a series of fortunate (for her) events, leaving behind an impoverished life in the countryside.As they get older, Roser and Guillem fall in love and she gets pregnant. Then he disappears during battle, presumed dead. Victor can see that Franco is going to take over the country and those with any kind of ties to the rebels could very well end up dead. So he convinces his elderly mother and Roser to leave Spain and head for France. Eventually Roser and Victor end up sailing to a new life in Chile, where much of the book is set. 

Truthfully, this book recounts a lot of history that I was only sort of vaguely aware of such as the Spanish Civil War and Pinochet's dictatorship in Chile, which was interesting. But at heart, it's basically a story of love and the strength of the human spirit.