Hey Pandas, What Is The Angriest You Have Ever Been At A Book? (Possible Spoiler Alert!)

I don't remember the name of the book series but it was a Sci Fi trilogy that ended in the protagonist and her love interest sacrificing their lives to save everyone else. Really unexpected and powerful for a YA book, but if course the epilogue had to ruin everything! Turns out the aliens were advanced enough to bring back the dead or something. They were given a second chance for their heroism. Ugh!! Then why have them make that sacrifice if it's ultimately undone!? It makes it seem trivial! I was so annoyed. They could have saved the world some other way in that case lol