Passchendaele (2008) on Netflix

In 1917, in World War I, the veteran Sergeant, Michael Dunne, is wounded at the front and nursed by Sarah Mann. He is diagnosed as neurasthenic and returns to his hometown, Calgary, to work in the recruitment section. When Sarah's asthmatic brother, David, is enlisted and demands that this be recognized by the father of his girlfriend, Cassie Walker. Sarah believes that Michael is responsible, and blames him for the engagement of her brother in the army. Michael re-enlists, using his mother last name, in order to protect David and they are sent to the no man's land at the front line of the Battle of Passchendaele.