Basically every Octavia Butler book, I love them so much. The most famous is kindred which is about real life slavery but it is not the most intese, I love all of them but the really soul crushing ones are probably Wild Seed (and the patternist series in general) and The whole Xenogenesis series (Dawn, Adulthood Rites, Imago). They all have themes of slavery and doing your best to survive and find a way out while utterly powerless, forced to deal with terrible things knowing that even dying would not change anything and so adapting to a terrible situation. There's usually a protagonist that values freedom, ethics, being a good parent, their people, and then a kind of coloniser character who has all the power and enslaves them, making them do all the things they would do anything to stop but they know that even if they died those things would still happen so they survive and try to do some damage control but ultimately they can't win