A friend who suffered trauma as a child sent me the talk "Complex Trauma: Understanding and Treatment" by Diane Langberg. I share it in the hope that it will help others.
The talk is available on YouTube. See here. (See also Narcissism and the Systems it Breeds and The Childhood Origins of Narcissism. A book I love because it shows what a relationship can be like between a son and his father—but rarely is—is Castle Warlock by George MacDonald. It's slow going, but it's deep, and it's warm. In his book, Heather and Snow, it is interesting to see how the victims of narcissism address the issue.)
The following sermon is about mental illness.
There is some great advice about how to interact with people who have a mental illness in Heather and Snow and the book Malcolm.