How should a person speak ill of you in front of me?

You can just go up and say with a smile, "I still have so many shortcomings. Let's talk about how many shortcomings I have."

If the other person is a respectable person and says those flowers with malice, he will definitely look embarrassed, so you will feel more comfortable. If he can continue to speak calmly, it means that the other party may think that your so-called bad words are not bad words in his view, but just some gossip. At worst, it can only show that his moral quality is not good, and such a person will just stop dating in the future.