After telling the girl that she was rejected, I felt that the relationship had gone bad. What should I do before I want to recover?

Talk to her. If you still want to be bosom friends with each other, tell her how you really feel. I think she will listen and explain that your idea is to let everyone understand each other and avoid misunderstanding. Apologizing and confessing are good ways to cure her. She also hopes that you can give up your wrong ideas. She needs friends badly. So you can go back to the past completely Your friendship is purest when you are honest with each other.