"The River of Sadness" Why did Gu Senxiang die?

Yi Yao received a strange text message, which said that if she was Qi Ming's girlfriend, then ask her to come to the school warehouse and tell her something. Yi Yao felt that Qi Ming's girlfriend should be Gu Senxiang, so he forwarded the text message to her. As a result, Gu Senxiang committed suicide because of this. In the novel, it is said that Gu Senxiang wrote this in a text message to Qi Ming before his death. I hate this dirty world. One can guess that something dirty happened to make her commit suicide. Later, Gu Senxi found the text message forwarded by Yi Yao on her sister's phone and felt that she had killed her sister. No matter how Yi Yao explained, he refused to listen and said very hurtful words. Yi Yao later went to Qi Ming to clarify the matter, but Gu Senxi told Qi Ming first, and Qi Ming did not believe Yi Yao and asked her to surrender. Said he didn't want to see her. Yi Yao said, okay, I'll let you see me now. Then she jumped to her death. But the end of the novel does not tell how Qi Ming died. Just writing, he wrote a few lines in his notebook, then turned off the light, unplugged the phone cord, walked to the kitchen, then returned to his room, lay on the bed, and slowly closed his eyes in the darkness. It seems that he committed suicide by turning on the gas.

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