In Six Chapters of a Floating Life, "Those who don't know each other are ashamed at first, and then they are unexpected." What does this sentence mean?

Trying to analyze people who don't realize each other will be ashamed at first, and then it will become unexpected. You and I don't know why this happened, and we are all beginning to feel ashamed. (To be continued) We didn't expect it to be so bad.

Language: Six Stories of a Floating Life

..... Those who didn't realize why the other party was ashamed at first, and then it became unexpected. I don't know what it means to accuse the old couple of being enemies. Or: "If not, how can we grow old together?" Is it true that Siyan is Qin?