YA Short Story - Woman Sends Bottles Downriver

The main short story featured a woman living in a cabin somewhere snowy. She would make ships (or maybe put messages in bottles) and float them down river where kids from town would find them. At the end of the story she grows weak and is unable to feed the fire. I think she freezes to death...

I read this more than a decade ago back in high school and it has been driving me crazy - any help would be appreciated!

No luck, huh? It was in a book of short stories I read back in 2008 or so.