The Chicago Manual of Style recommends not replacing colons with commas in dialogue if the intended meaning is a long pause or illustrative expectation. Instead, I'll correctly apply other punctuation rules from The Chicago Manual of Style.
Listening to Gu Yi'an finish, Jing Si was completely dumbfounded.
"So, you just married yourself off like that? Married someone you barely know?" Jing Si's voice carried a distinct note of gritted teeth.
"Yes, Consort Jing."
Seeing Gu Yi'an's calm demeanor, Jing Si was about to lose it, staring at Gu Yi'an with a look that screamed "disappointed beyond words."
"You... you just don't stop worrying people, do you!" Jing Si said, rather helplessly.
Gu Yi'an's lips twitched, wondering who was more worrisome right now.
At least after experiencing the thing with Lu Moran, she wouldn't easily have her heart moved, and without a stirred heart, there wouldn't be heartbreak.