A large part of it, yes, because Kael is Hestia's favorite character and she saw Kael literally commit suicide and she had time turned back for him. That's why she's hell-bent on seeking revenge for Kael and why she hates Diana so much.
After Diana (pink hair) and Helios got married, they didn't care enough to check up on their "friend" Kael, and that drove him to suicide.
So in the original, Kaelus was the second lead, and undertook all the real responsibility the prince shrugged off. There was a serious threat to the empire and kaelus decided to have someone or some group killed, and Diana being the saintess said some shit like "I will not tolerate such evil around me", practically socially exiling Kaelus, painting his as a bad man, and broke his heart. Because its a dramatic romance, kaelus ended up killing himself in the og timeline. Now the FL, Hestia, is on the block, she's like "Kaelus is my favorite man, imma make the saintess feel all the pain my favorite felt," and here we are. Hestia's hate boner for the saintess is growing even harder cuz the saintess is an delusional crybaby- i think I got all the bases covered
Not just rejected him. Pink hair basically led both the ml and the crown prince character on, knowing she would only be choosing one of them for her own benefit. When the one she ended up choosing wasn't the ml, he killed himself in the original storyline. Because the fl loves the ml character, she hates pink hair for driving him to do that and wants to see her suffer and lose everything
am confuse it been a long time since i read this, so am wondering why does the fl hate the pink hair so much. is it just bcs she rejected the ml?