In Wide Sargasso Sea, it is very clear from early on that race is going to be a big topic looked at in the book. The Emancipation Act was only recently passed, and the Cosway family has not received the compensation that they were due from losing their slaves. With old Cosway dead, the rest of the family is left in financial ruin, and this is something noted by many people around the Coulibri estate. The Cosways are thrown into the lowest socioeconomic class until Annette remarries a rich Englishman. But they are one of the most hated families in the area; ex-slaves still hold resentment for being held as slaves, but also for old Cosway's explorations into slave women. The upper class now dislikes them because they don't like that someone from outside their class was brought into it. So, Cosways probably won't have an easy time making friends with anyone.
Something that really struck me about the situation that the Cosway family was in was the term "white [n-word]." I think this is very interesting because the ex-slaves see people like the Cosways as even lower than they were. Tia explains this quite well when she and Antoinette are ending their friendship: "Real white people. they got gold money...Old time white people nothing but white [n-word] now, and black [n-word] better than white [n-word]." Because the Cosways have fallen out of the upper class, Tia and her friends and family see them as the lowest of the low. The Cosways are social and economic outcasts, there seems to be no place for them anywhere. The upper class made of stuffy old white people don't want contamination from the lower classes and the lower class made of ex-slaves don't want anything to do with white ex-slave owners.
The Cosway family doesn't experience much trouble that comes from outside of these issues. Pierre dies because a drunken mob of ex-slaves. These ex-slaves, for reasons not totally known had decided to make an attack on the Cosway family and estate, first setting fire to the room where the already weak Pierre was sleeping, causing the entire house to burn down, and then attacking the fleeing Cosways. Antoinette, during this scene has a sense of the reason they are being attacked. She knows that everyone hates their family, and this is why she runs to Tia with the hope of being let into their family. She wants to escape hers so that she can have friends and be liked and no longer attacked. But we know how that turns out. Tia has been indoctrinated into the ideas that white people are evil and poor white people are the absolute worst, and so she throws the stone at Antoinette, rejecting Antoinette completely from her life.
Antoinette was born into a very unfortunate situation where, if this were the Indian caste system, she would be an "untouchable" even though her family was previously well enough off. She has no chance of making friends due to the passing down of hatred from parent to child. The only place that seems fit for her is the convent where she is only thrown because her family is all dead or gone away.
