UK(?) film, as seen on Netflix in 2014… stumped!!

Hi and thanks in advance for reading…

my wife and i were searching for a movie to watch in fall 2014 and found a list of “international movies on Netflix” that are worth watching. we picked one and watched it and it was great, very powerful acting from the young female protagonist. we haven’t been able to find the movie again, thinking about it for the past few years.

What we know:
It is set in ireland/england, forget which.
The movie basically takes place in a cul-de-sac in a neighborhood. The main character, a special young teenage girl (12-13 yrs?) lives with her older high school brother and parents. This girl has diabetes, or some other type of underlying health condition. Important neighbors in the film are an autistic/developmentally delayed adult man living with his parents, and in another house, some popular/promiscuous older teenage girls. The film is a coming of age type story with the protagonst, as life unfolds around the culdesac. her brother impregnates one of the neighbor girls. that girl later has a miscariage at a party.

there is a treehouse/clubhouse in a field/forest type area that is “no adults zone” in the film, the children have various experiences out there.

the main conflict event of the film, is when the main character is held captive by her autistic neighbor, in his house. she feels sympathy for him, and goes into his house, where they “play” together before something triggers him and it turns into a captive situation. we think this man may have accidentally killed his mother during this whole situation. the situation turns dire as the main character’s diabetes, and lack of medicine, causes her to lose consciousness, and is tragically left to die in a locked room, where nobody knows where she is. she is found and rescued by her father, and rushed to a hospital.

i won’t give the ending away.

WILL ANYONE HELP US IDENTIFY THIS MOVIE??

we watched it in october 2014 on netflix. it was made sometime after the year 2000, i think. it was an indie film, but had a decent production budget, it seemed. we were familiar with no actors or companies associated with the film.

i seem to think the movie tite was one word, the protaganist’s first name…. “Emma”? I could be way off on this last one.