One, the father's mad because people are talking rumors that are completely true. Instead of having any shame, he blames the people talking and saying the truth.
Two, our MC flat out states that her problems will be solved if he stay the F away from her. (although it's too late as the princes has already begun to move, and staying away didn't really help all those other girls that the prince wasn't even interested in)
It's kind of sad she second guesses herself
Three, he actually thinks he can protect her? Is it that he just let that crazy princesskilled people and ruin the lives of whole families without care, but NOW that he likes a girl it's worth his time protecting? What a shit person. He has made no effort to protect anyone before because politics? Cold bastard, our girl can do better.
Edit: four, why is she staying in that city? Before it was because she needed to stay near to protect her Mother, but now they are out of the Su house, they should have left, maybe even to another country.