Back in the day, he was not initially aware of Qin Zhiyou sneaking around and harassing Lu Weixi. Then, he broke up with Lu Weixi; they had sex. Soon, he realized that his breakup with Lu Weixi had been a misunderstanding. But by then, she was already living with Qin Zhiyou and they were discussing marriage. Even with the thickest skin, he could not ask to reconcile.
On reflection, however, even if Lu Weixi had wanted to get back at him through Qin Zhiyou, surely he wouldn't have fallen for it so quickly. At the time, he and Fang Rushuang were deeply in love after they started dating and got engaged, he had brushed off all other women. Who knew that as soon as he slept with Lu Weixi, he called off his wedding, dumped Fang Rushuang, and moved in with her? He immediately cut off from Fang Rushuang and never looked back.