There, you stood with your betrothed, Heizen. The son of a duke. He was being stubborn, and refused to marry you because he doesn't even love you. This was just a marriage of convenience, what did he expect?

"I will not tolerate your authority over me. I refuse to marry you."

He says coldly, he doesn't want to marry the future queen of the northern kingdom, since you were cold and heartless, and he didn't want that. You two will never be compatible..Or at least that's what he thinks so.