I believe what disturbs people regarding the title is their assumption that "Catholic" solely pertains to the religion. McCarthy's family was Catholic, and she attended a Catholic school for several years. HOWEVER (and this is of great significance), I also think McCarthy is referring to the adjective "catholic" (with a small c) here.
This time, my favorite chapter is the final, extensive one about her grandmother. It is a detailed and beautifully descriptive tribute in which she endeavors to capture their complex relationship. It appears to be the most genuine story in this collection.
After each chapter, McCarthy includes an account of what she knows to be absolutely true in the preceding chapter, what details she is unclear about, or what she outright invented to create a good story. It is an interesting way to read a memoir. I love it because it reveals the aspect of McCarthy's personality that is determined to seek the truth.
All these stories are excellent, and the one in which she relates the tale of her abusive Uncle Myers is, more so than the others, particularly heart-wrenching. He is dreadful, but she verbally decimates him, presenting him as the most pitiable character. Her descriptions of what they did as kids for entertainment are hilarious; for instance, "went to the park to watch other kids ride the ponies because that was free."