Run Yu's self reflections and Xu Feng's moral dilemmas

Run Yu is the most elaborated character of the drama (which gives Leo Luo plenty of opportunities to show his acting skills, and he's done it masterfully). I love his self reflection in the dialog with Kuang Lu: "have I really changed?" However, Xu Feng's moral dilemma around his mother is something that doesn't cross my cultural barrier. How does his mother crimes deal with HIS conscience?