Série de livros distópicos: menina sai da barreira em que sua sociedade vive por causa da radiação

Era uma vez estrelas e também

É muito estranho, mas isso quase certamente tem que ser Era uma vez estrelas, de Melanie MacFarlane.

• Protagonista feminina.

• Mora com a avó:

  The clock on my dresser reads eight o’clock in the morning. It’s been nine years since I moved in with my grandparents, and saying Grandmother and I have differing opinions barely touches the surface. Her rules are sometimes worse than those of the Order, who police the dome. With any luck, I’ll be assigned my own apartment soon, and will finally be able to restart my life again.

• Em uma cúpula:

  I trace the row of stitches, squeezing my eyes shut as I make a wish; it is my eighteenth birthday, after all. But when I open them, the same scene shows from my bedroom window that always does—the grid of our dome. Nothing changes. It doesn’t matter how many birthday wishes are made; I always wake up trapped inside the dome. The grid of thick glass and steel arcs far above our apartment, stretching to where the great Axis, a tower of government offices, meets the peak of our home—Dome 1618.

• E ela vê uma luz do lado de fora da cúpula, onde ninguém deveria estar (reconhecidamente, não à noite):

  Another light flashes, but this time it’s in the distance, on the other side of the glass. I lean forward, focusing on the light, and see a shadow move on the other side. My entire body goes rigid, and my heart beat thunders in my ears. No one could be out there—unless—could it be an Infected?

• Por causa da radiação:

  They were all killed by the Cleansing War—everything was. If the nukes didn’t kill them, the nuclear fallout afterward would have.

• E o protagonista encontra seu caminho para fora da cúpula.

• E ela fica para trás enquanto o protagonista foge com um menino:

  We make our way outside the dome. When I feel the open air against my face, I know I’m finally free. The night sky stretches out above me. The moon and stars light my way toward the life my mother wanted me to have. I turn and see other people flowing out of the open dome. In the distance, I can hear music in the air. People are celebrating.

  I look out into the skies of the mysterious beyond. My fingers reach over and entwine with Evan’s. I whisper, just loud enough so he can hear me.

Eu acho que o pôster pode estar misturando isso com também, que visualmente tem a descrição que eles mencionam:

Foi publicado há alguns anos e está em uma série de livros com títulos simples. O elemento de algum parente se apaixonar por alguém fora da cúpula pode ter vindo de lá (não se lembra).

No entanto, o primeiro livro foi publicado apenas seis meses antes desta pergunta, que parece muito pouco tempo para lê-lo e esquecer o suficiente para confundi-lo com outro livro.

Acho que encontrei o que você está procurando. É uma nova série chamada Ido (2008) de Michael Grant.

A partir de Goodreads:

There are teens, but not one single adult. Just as suddenly, there are no phones, no internet, no television. No way to get help. And no way to figure out what's happened.

Hunger threatens. Bullies rule. A sinister creature lurks. Animals are mutating. And the teens themselves are changing, developing new talents—unimaginable, dangerous, deadly powers—that grow stronger by the day. It's a terrifying new world. Sides are being chosen, a fight is shaping up. Townies against rich kids. Bullies against the weak. Powerful against powerless. And time is running out: On your 15th birthday, you disappear just like everyone else...

Eu acho que sim. Você também pode consultar Wikipedia.