maybe the curse is supposed to end all magic.
He also told Cinderella that the fairy godmother’s wand was pure evil. I think he want’s to get rid of all magic- not just to break his curse- but because he really believes all magic is evil
As for why he needed someone else to break the curse, If true love is needed to break the curse, he would need another person since he believes no one is capable of loving him.
[adrotate group="5"]