Family is still very important.
Even though Barcelona has nothing left for Andrea, she has to work through an entire emotional process to finally gain the resolve it will take to leave them behind. And Andrea's decision is not depicted as callous or detached, but rather, she is left with difficult choices to put her own interests above the social obligation that family represented in 20th century Spain.
War redistributes wealth somewhat randomly.
The character of Ena is an important foil to Andrea's family. Ena's father can provide a future with a career and continuing education, whereas Andrea's family lost their wealth, leaving her in the aftermath of devastating losses.
The government is a mixed bag.
Unfortunately, the Spanish Civil War did not eradicate the social and political problems that preceded it, and in fact, Spain under the Francoist regime was highly suppressive of freedom of speech and behavior. There's a reason why Uncle Roman would rather die than fall into the hands of the government. But for Andrea, the government allows means stipends to help her afford school and pay her bills. So the government is being depicted in a truer, more inclusive way, showing the challenges of existing in a post-war regime.
Existence comes before essence.
This novel was part of an existentialist movement in Spain, not because it is openly philosophical, although it is thoughtful, but rather because it deals very centrally with the elimination of the old ways of thought around why life exists and what the purpose of life is in the lives of individuals. Andrea's decision to start over with a new adopted family in Madrid is a perfect depiction of this. She recognizes that objectively, even though things happen with a sense of order, that order cannot be authoritative, and in fact, it's probably contrived. This is why she allows herself to do what is in her best interests instead of watching the final deterioration of her family.
