Watching ep 24 now. Why she has to leave just because of his uncle? So she think Sang Yan cannot handle her uncle?…
The reason she left is to protect sangyan bcoz that garbage uncle is already ruining sangyan business, she doesn't want sangyan to suffer, so she left to protect him. Also she has trauma and it got triggered. Sangyan does know a bit about her family like her dad dying and how her aunt bad mouths her it was shown in earlier episodes, what he doesn't know is her living condition and the SA from that garbage uncle, it makes sense he doesn't know this bcoz its too personal like just bcoz you know someone doesn't mean you will know everything about them 100%, we all have secrets lol so it make sense.