If I can remember, the movie is about a man who went to the Vietnam war and left his wife and children. He was presumed dead during an explosion, but he had survived. His wife remarried his best friend. However the man came back and tried to search and convince his wife that he did survive. His wife was only convinced when he played their favorite song on the piano, and after he smoke, he would leave one cigarette left in the packet. The movie came out maybe in the late 1970s or early 1980s