Now we know why Yuki is so shy and insecure, her mother overprotective behavior.
Uh, no, we've had ample enough flashbacks of the kind of unwelcome attention from strangers it's mainly rooted in. But her mother's intense and formidable personality is unlikely to have much helped - it's only too easy to picture how a kid as timid as Yuki would have been unintentionally overwhelmed by such a parent.
Also bit of a chicken and egg thing as there's certainly no shortage of objectively valid reasons to worry about the kid, only compounded by the mother's frequent extended absences due to work and their awkward relationship creating a serious communications barrier. Case in point Yuki's been working at Nekotamari for, what, half a year plus without apparently bothering to notify her mother of it even as a courtesy - I reckon a parent doesn't need Ms. Shirakabe's mercurial temperament to kind of start bouncing off walls over something like that. (TBF she's probably unusually agitated atm due to both having been left out of the loop about a fairly important developement and being worried sick.)
It also reads like pretty textbook teenage chafing for independence and rebelling against parent figures. ie. part of growing up. I'll be rather surprised if this isn't primarily a character growth arc for Yuki as the family grapples with the various anxieties and personality clashes involved.