heart crushing

An act of emotional violence, usually committed by a book, which leaves the individual experiencing it both elated and devastated simultaneously.

In my book, there's a lot of intrigue and thrill and SHE'S TRYING TO KILL HER AND HE KNOWS IT BUT HE DOESN'T WANT TO TELL HER AND HE CAN'T LET HER GO BUT HE LEAVES HER IN DANGER IF SHE'S ON THE CASE AND IT'S ALL SO HEART CRUSHING.