I love Nanny Fiona Fang. Why did she break up with Ma Shuer?

Ma Shuer's son Ma Jimo suffers from leukemia. The best treatment is to have a baby with Lin Yue (umbilical cord blood or something). Ma Shuyun thinks the death of his son Ma Ji is extremely important. Fiona Fang is convinced that Ma Shu Yun would rather give up his love in order to save his son. Persuaded by Fiona Fang, Ma Shu Yun left the cinema with a heavy heart, with his beloved man on one side and his beloved son on the other. If given a choice, she thinks she will choose her son. As a matter of fact, Fiona Fang has offered to end her relationship, so let nature take its course.