
Isn't the tragedy avoided if she doesn't become the empress? Or does she want the revenge?

That and she probably realices the risk of letting a murdering, scheming and backstabbing ruler run her country, in a kingdom where her noble family is evidently still somewhat powerful and prestigious enough to to offer an empress candidate, and thus to be seen as a threat by the emperor and covertly attacked…
What a piece of shit
Just switch to jinhyuk. He seems sweet