Ah, you’re in luck…that’s one of the few books I haven’t managed to pack yet…
The story is called “The Last Pennant Before Armageddon”. As the title implies, it’s not even the Cubs WINNING the WS that will cause the end of the world, it’s them just making it there.
Seeing as I’m a Cubs fan, you have no idea how true this idea rings to me…
Margaret Atwood’s “A Handmaid’s Tale” probably qualifies. It’s not the end of the world entirely, but there are big big changes afoot in society. Creepy.
There is an interesting children’s book called “The Girl Who Owned a City” about the aftermath of an epidemic that only killed people over 12. It’d be a quick read but, as I recall, a good one.
I seem to remember reading an interesting story a looong time ago. Perhaps in gradeschool. It was called Z for Zachariah. It was about the only girl left in a small town after nuclear war.