All the Ways We Said Goodbye by Beatriz Williams

The New York Times bestselling authors of The Glass Ocean and The Forgotten Room return with a glorious historical adventure that moves from the dark days of two World Wars to the turbulent years of the 1960s, in which three women with bruised hearts find refuge at Paris' legendary Ritz hotel.
The heiress . . .
The Resistance fighter . . .
The widow . . .
Three women whose fates are joined by one splendid hotel
France, 1914. As war breaks out, Aurelie becomes trapped on the wrong side of the front with her father, Comte Sigismund de Courcelles. When the Germans move into their family's ancestral estate, using it as their headquarters, Aurelie discovers she knows the German Major's aide de camp, Maximilian Von Sternburg. She and the dashing young officer first met during Aurelie's debutante days in Paris. Despite their conflicting loyalties, Aurelie and Max's friendship soon deepens into love, but betrayal will shatter them both, driving...