These Deathless Shores by P.H. Low

Jordan has gotten good at pretending.

On an Island where boys fly and fight pirates, but girls can only be mothers, Jordan's shaved head and false swagger are the only things keeping her adopted crew of Lost Boys from forcing her into a role she has never wanted. When she gets her first period, she's exposed and thrown back Outside—into a world where grown-ups die slowly in offices, flight is a fantasy, and withdrawal from the Island’s magical Dust slowly strips its afflicted of their dignity.

To Jordan, it’s a fate worse than death.

Nine years later, when the drug she has been using to medicate her withdrawal begins to show its fatal final symptoms, Jordan persuades her best friend and fellow ex-Lost Boy to return with her to the Island. With the help of a temperamental pilot and her long-estranged sister, she sets in motion a plan to oust Peter from his throne and seize control of the Island’s Dust supply.

But Peter isn't the only malevolent force moving against her. As Jordan confronts the nature of Dust, first love, and the violent legacy carved into the land itself, she realises the Island may have plans of its own...