Her "unbearable" and "dirty" background was an unspeakable humiliation to Song Mingzhao and the entire Zhenguo Marquis Residence.
However, her marriage with Song Mingzhao had been arranged by her elders. The two Matriarchs who had been involved had already passed away and tied a dead knot in this marriage.
The Zhenguo Marquis Residence was also a family that cared about their reputation, so they couldn't do something like "reneging the marriage". That would mean going against elders and being heartless. They could only pinch their noses and admit in an aggrieved manner that Song Mingzhao had to marry her.
Song Mingzhao was a prodigy and cared about Yu Jianjia. How could he tolerate marrying a woman with an "unbearable" and "dirty" background?
No other man could accept it.
In Song Mingzhao's opinion, she had an "unbearable" background, snatched Yu Jianjia's position as the first wife and reduced the woman he loved to a second wife.