She knew he was injured and he was pretending, it's exactly like in the mortal realm.
"It's just a scar, Liu'er"
"No need to worry, I had worse,"
When he is really injured, he didn't tell and when he is not....he would trick her, so she would stand a little closer or sleep a little closer. Feed him by herself, it always uses to down at her a little late and sometimes never. When she recognizes it, she can't help but willingly get tricked. In the end, she always falls.
Now she is scared out of her wits and there was nothing or no one who could reassure her. She enough that's she can't boldly go in and ask for what's is going to happen. No one is going to help her or let her interfere. Ren will refuse straight out, Aunt Tai with GuGu will probably tie her down until this is all over.