Girl in _Progress is actually a very simple, straightforward story about a young girl doing her best to cope with her own adolescence as well as her not-much-older mother who, in actual fact, is doing almost the same thing. Due to her history (harsh, non-understanding mother), Grace (Eva Mendes), is desperately trying to find the love that she didn't get when she was Amiestad's age - and why shouldn't she?
I suspect that this movie is a lot closer to real life than a lot of viewers realise. Teenagers forget that their parents have given them the very best years of their lives form the time they were born right up to the time they think they know everything - and then some more! Fortunately Amiestad realises this a lot sooner than many kids her age but not before hurting her bet friend unforgivably (even though her best friend DOES forgive her!)
In this film, mother is only about 34 or 35 and still a beautiful woman who has the very same needs as her daughter - although her daughter (initially) totally fails to recognise that fact. Like many teenagers, she thinks that the world revolves around her - but it doesn't and, at least in this movie, she finds out before it's too late.
I would suggest that this should be compulsory viewing for all adolescent kids but I fear that, in a lot of cases, they would shrug their shoulders and just say, "Whatever!"
As Ned Kelly said when told he was to be hanged at ten o'clock the next morning, "Such is life!"