That said, my next book choice will definitely involve happy puppies and no one getting hurt.

Firstly, I know how you feel! Last week, I was reading All Quiet on the Western Front, The Heart is a Lonely Hunter and a memoir of alcoholism, and oof, the combination of the three got me down. Hope you found something suitably comforting for your next read!

I'm intrigued by the fact that I'm interested in finding some Hunger Games fanfic, but at the moment have no intention of rereading the books, because I just don't want to put myself through that again. The constant suspense and agonising twists left me exhausted.

I've read the article linked in the comments above, and it doesn't convince me. Or if the author intended us to read that way, where was the confirmation that the "last" games didn't go ahead?

I also wondered about Katniss's agency. By the end she's clearly beyond her limits - beyond anyone's limits. All the way through, she was extremely reactive because that was what was needed. But has that left her with anything at all to be happy with, once everything is over? Yes, the epilogue shows that she had a measure of happiness, but not much more than that.