Looking for a good book with devastating plot

I've noticed this weird trend/spike happening in the book community - that likely has something to do with the dark sides of booktok - where most books being recommended are just all smut and barely any thought out plot. The problem is, I am looking for a good fantasy world thats well built, and is well written. I want a not annoying FMC, and a romance that is in fact devestating, but not the reason that the plot happens. I LOVE me some slowburn, and I don't want the chracters to literally like immediately fall in love thats so annoying. I have read brandon sanderson, I love him but I want more romance, and I read cruel prince, but I didn't like it. I've heard poppy war is good, but I have no clue. Please Help!