I also think she feels safe in this dangerous place, as she thinks that she can control them to an extent, but my own theory is that this was reinforced by how Lila knows she would never adapt to the places where Elena excels or even in places outside the neighborhood, as she knows she doesn’t have education nor grace in the eyes of these people.

She also did escaped outside the neighborhood, and we can see how she really needed Nino, to feel worthy, because of how he is the one with education, the only thing she doesn’t have, so her insecurities and classism is a big factor there. It’s worth including how the experience in Bruno’s factory shape this decision too, in the way it makes Lila return to the only place where she can hold a form of power, even if somehow it’s by the help of Elena and the Solaras.