The Villain Doesn't Follow the Plot

Valerian lost her mother at birth, and her family has always despised her for it. The only person who treated her with kindness was the crown prince, to whom she was betrothed. However, everything changed with the arrival of her cousin Marlene, who quickly won the affection of both her family and the prince. This caused Valerian to become a villainess, attempting to kill her cousin out of jealousy.
But now, a new soul has been reborn in Valerian's body, and with the knowledge of her unfortunate future, she decides to distance herself from her family and break off her engagement to live a better life. To her surprise, however, the crown prince, Callisto, has come after her and has no intention of accepting the broken engagement. Why is Callisto so insistent on her? What are his true intentions?