Because of the way these three movies were shown on television yesterday, I saw 1918 first, then On Valentine's Day, then Courtship. This is the reverse order of the chronology portrayed, but it was extremely helpful in other ways.
In 1915 Harrison, Texas, an as-yet-unkissed piano teacher in her twenties is stymied from finding romance by her snobbish, suffocating parents whom she still lives with. Screenwriter Horton Foote adapted his one-act play, originally part of his nine-play saga "The Orphans' Home Cycle", and apparently had a hand in the casting as well (Horton Foote Jr.