What do you mean by "The POV is 3d person, adult, in the protagonist's mind."? If you mean that the narrator is an adult looking back on her teen years, then it probably is an adult book. If the narrator is still a teen, very possibly it's YA.

But "YA literary fiction" is a thing. Check out books like THE F1RST TIME SHE DROWNED, which I believe (haven't read it) is also about an abusive mom.