Obviously there's a lot of unpleasant things happening in Wide Sargasso Sea. The main character, Antoinette, has had a poor family life with a distant mother and no father. This is only the surface of the situation, since what Antoinette has of a family is one that is shunned for its past and present. Her father was a wealthy slave-owner who is reviled for his drinking and adultery, as suggested by the "smooth smiling people" Antoinette hears gossiping as a child (25-26). The awful person that Mr. Cosway was is confirmed by his illegitimate son Daniel, who resents him for being a cruel slave-owner who ignored his children and bought and sold people "like cattle." (111) Now that Mr. Cosway is dead and the Emancipation Act has been enacted, Antoinette's family has become destitute and their change in social status has alienated them from whatever white upper-class they were once part of. Antoinette's mother is considered to be mad, which invites further suspicion from about everyone around. To sum it up, Antoinette's family is hated for her father and their role in slavery, and how they are presently poor and white. Their situation alienates them from the black and white people around them.
Antoinette experiences a lot of this ill will as a child through both actively experiencing it (hearing gossip, being threatened or called names) and just being shunned away in her home (her mother is aware that they are hated). While this unpleasant situation pervades her childhood, Antoinette has a poor relationship with her mother. Antoinette remembers her mother saying "Let me alone" when she tries to interact with her (18). The excerpt "I started to fan her, but she turned her head away. She might rest if I left her alone, she said," is particularly revealing. The closest relationship Antoinette has is with Christophine, her mother's "wedding present" from her father (19). She is a black woman unrelated to Antoinette, but cares for her when her own mother is unable. Antoinette cares a lot about Christophine, as she interacts with her often in adulthood, and as a young child she was too afraid to ask her mother about Christophine leaving (20). As Antoinette grows up, her mother passes away and she tries to not think about her.
I think Antoinette's difficult relationship with Rochester has a few allusions to her relationship with her mother. Again Antoinette is being ignored and interacting little with someone she's supposed to be close to. The question she asks Rochester--"Then why do you never come near me? Or kiss me, or talk to me,"--could also be asked of her mother.