It was a love letter. But it wasn't one of those my darling I miss you I can't live without you gushy letters people write in the first flush of love. When I checked the postmarks, it was apparent the letters in the bin went back several years, and they were all from the same fellow. Larry.
As for the car crash: some googling called up a page about Edith and Kenneth Rowe, who died Dec. 24, 1937 The storys says "Edith and Kenneth died Dec. 24, 1937 in Worthington, MN just after attending a business Christmas Eve party for her husband's work at Arnold Motor Supply Company in Marshall, MN. After the party they were on their way to Lake Park, Iowa where their children were in a Christmas Eve play."