With her commander pressuring her to submit to marriage, Khadija decided she needed to leave the brigade.
"So it was at this point, I said enough. After all that I had already seen and all the times I stayed silent, telling myself, 'We're at war, then it will all be rectified.'"But after this, I decided no, I have to leave."
Khadija left just days before the coalition airstrikes, but her family remains in Syria.She was smuggled across the border to Turkey.
Khadija still wears the niqab, not just to conceal her identity but also because she's struggling to adapt back to life outside the Islamic State. Regretful of her immersion in radical Islam, she is wary of another sudden change.
"It has to be gradual, so that I don't become someone else. I am afraid of becoming someone else. Someone who swings, as a reaction in the other direction, after I was so entrenched in religion, that I reject religion completely,"
"I don't want anyone else to be duped by them. Too many girls think they are the right Islam," she said.She desperately wants to be the girl she was before falling under the spell of ISIS --
"a girl who is merry, who loves life and laughter... who loves to travel, to draw, to walk in the street with her headphones listening to music without caring what anyone thinks," she said.
"I want to be like that again."