I’m guessing that Shizuka and her mother will come out of this with an improved relationship, which means the story will go one of two ways. The first is revealing that the mother isn’t actually a shitty parent, probably by adding her POV of her yelling at Shizuka and hitting her in the past. The POV would probably be something like “the mom was being criticized by other mothers for having a creepy kid”, or, since we haven’t seen any trace of Shizukas father, “the mom was criticized/blamed for the way Shizuka was.” (could also be like “it can’t be helped if her daughter is like that. she is a single mother after all.”The backstory could also be that the mother was just worried about Shizuka and went about it the wrong way.
The second way the story could go is just having the mother being a shitty person who realizes at end that Shizuka is socializing and communicating (albeit in a differnt way than shed like).
I’m guessing we‘ll go down the first path though.