Beatrice and Ruth have a very problematic relationship. It is easy to see their personalities are similar, and this causes them to clash frequently. They are both outgoing, vain, and very sensitive to what others think about them. Beatrice talks about her younger days and how attractive and popular she was. We learn from Ruth that some people in the community used to refer to her mother as "Betty the loon." When Ruth repeats this in her mother's presence, Beatrice is visibly wounded and upset. It is obvious this gossip causes pain and humiliation for both of them, but Ruth retaliates against her mother's criticism of her by taunting her with this information.
Their relationship is characterized by oversensitivity and hyper-criticism; it is volatile, dysfunctional, and often passionate. Beatrice is protective of Ruth due to her illness, but just as Ruth is ashamed of her mother, there seems to be some embarrassment on the part of Beatrice because of Ruth's ailment. Clearly, the similar personality traits and psychological issues affecting both women are a factor in their relationship. There is also shame connected to Beatrice's husband leaving her years ago, and Ruth's interest in boys is overshadowed by her mother's failed marriage.