At the Gu residence.
No one from the Gu family went. Since Gu Jingze had already left the Gu family, they didn't want to get involved.
The main reason was still that they were very concerned about their reputation. During this period of time, the Gu family had kept telling the outside world that Gu Jingze was the one who had betrayed the Gu family, and thus they wouldn't maintain good terms with a traitor.
Moreover, they were arrogant and thought that the Gu family was the strongest. After Gu Jingze left the Gu family, he was thought of as nothing.
After the Gu family announced Gu Jingze's betrayal, they had no idea how many people would still attend his wedding.
However, the Gu family soon got the news that many people were attending the wedding.