I went by the reviews - I don't intend to read the book. Her husband believes she suffered from borderline personality disorder. Have you had a friend or family member with BPD, or another cluster-B PD?
These are clinical standards for self-absorption and toxic personality traits. In their relationships, cluster-Bs select for supplicants who will love them despite their toxicity. What you're saying about the memoir is consistent with this.
Her mental health conditions aren't a reason to disregard everything she says, but she is providing social and interpersonal advice here, in a way that is likely to encode the dysfunctional schema and disordered thinking she suffered from in life.
For an opinion piece that is about how to empathize with other people, I think it is relevant information that the author probably had a clinical impairment in their own ability to empathize with and understand others.