Sadly predictable.

Spoilers ahead:

Not sure how I feel about this movie. I found it mildly enjoyable and the acting was very good in my opinion.

But on a global level the story kind of fails because it's both predictable and inconsequential.

The predictability would be less troublesome if there were a "lesson" or consequences for actions and circumstances, however at every turn very serious and dire events are basically "shrugged off".

A slutty, immature mother and an irrationally combative AWOL father produce a predictable daughter with predictable issues who finds herself in predictable circumstances.

Yet the circumstances (promiscuity, rape, daddy issues, etc) lead to unpredictable, benign results.

My problem with this movie is that the actions and circumstances actually seen in the movie doesn't mix with the "bigger life".

The movie makes it seem like the girl's "coming of age" is something standard or normal that everyone can relate to.

Most girls don't go from having virgin to 3 sexual partners in a couple of months. Most girls don't count a rapist as one of those partners. Most girls probably wouldn't turn around and start a relationship with the rapist's best friend. A girl who does all of that probably wouldn't end up where the movie acts like she is going to end up.

In reality:

At the end of the summer, the daughter goes back to school with a rapist and a likely reputation as a slut herself. Mom's back home, divorced or separated, perhaps poorer depending on the circumstances of the separation. The Daddy issues are only going to get worse. The mother's and daughter's promiscuity are both likely to escalate. Nothing was solved, in spite of her final happy internal monologue. As soon as the camera shut off everything continued to degrade.

This movie is about "unstable families" per the opening line, but it seems to trivialize the circumstances that are created by those unstable families.