Ethan ended up badly injuring Shadow Stalker and escaped to look for his wife and kids only to find the house empty with a Dear John letter.
A coming marriage that was broken by a Dear John letter is believed to have played a role in his breakdown per The Oxford Companion to Chess.
The pictures all depicted the same scene in a bar (in which a man burns a Dear John letter), and each photo was taken from the separate point of view of someone who appeared in the other photos.
Meanwhile, Julie gets engaged to another man (named Peter), and writes a "Dear John letter" to Wally while he's still on his mission ("He's Just a Friend/Dear John").
Leaving behind a fake Dear John letter for Bart Allen, that as expected prevented him from questioning Valerie's disappearance and search for her whereabouts, he took Valerie into an unknown location, hoping to use her DNA to restore his appearance, and use Valerie as a bait to take his vengeance on Bart, with Inertia's aid.
John F. Kennedy | Pope John Paul II | Elton John | John | John Lennon | John Wayne | John McCain | John Kerry | John Cage | Olivia Newton-John | John Williams | John Peel | John Adams | John Steinbeck | John Travolta | John Milton | John Zorn | John Marshall | John Howard | John Singer Sargent | John Ruskin | John Updike | John Maynard Keynes | John Coltrane | John Cleese | St. John's | John Waters | John Lee Hooker | John Huston | John Ford |
The song played on the concept of a Dear John letter while referencing the United States' involvement in the Korean War.
Meredith learns of her condition from Dr. Steve Hardy (John Beradino) and wanting to spare Larry the pain of watching her die, Meredith ran away to San Francisco and left him a "Dear John" letter saying she didn't love him any longer.
Lisa has married another man (her "Dear John" letter to Andy apparently never received), and a friend entrusted to take care of the motorcycle track business (Mack, played by Jimmy Dean) has made arrangements to sell it out from under Andy.