Trash

I'm sorry but this is just trash. I can't, she is really going to forgive and forget everything they did (and yes they, those 4 assholes are accomplices) he is supposed to be a crown prince but is just a tyrannical narcissistic piece of shit asshole, white hair just blackmailed her and only help her cuz she was interesting and for him to keep the secret she has to keep him entertained.
And she wa supposed to be the strong female lead character that gets revenge on the suffering that they put her and her family through but noooooooo now she's just becoming incredibly stupid (which now i think she always was), and a blushing maiden to the people who tormented your Younger sibling and killed you and your Family. Nah fuck that, they can have the most tragic backstory known to man but that still does not give them the right to be compete human trash.
At that point just kill them all the whole kingdom is trash if thats who will take over.
A much better ending would be if she lives happily with her Family and a man that actually loves and cares for her, which if she doesn't change, her poor husband is gonna suffer too.
Sorry not sorry if this offends anyone, if you like this, well to each their own, but you need to read better stories.