People who appear to wallow in their suffering are unattractive, but describing Elizabeth Edwards as "Scum" is extremely harsh.
Mrs. Edwards perceives herself as the role model of suffering and seeks attention (perhaps sympathetic accolades) and remembrance as the grieving mother who lost a child (and yet she survived), as the deathly-ill woman who is/was afficted with cancer (and yet she survived), and as the wounded wife who was betrayed by an unfaithful (victimizing) husband (and yet she survived). Hence, the title of her book: "Resilience: Reflections on the Burdens and Gifts of Facing Life's Adversities." Some people simply thrive on the drama of "victimhood" and all the attention they get from it. It's a narcissistic quality often associated with factitious disorders.
In an interview with Matt Lauer, Mrs. Edwards claimed that she wants to be remembered by her children as a strong (resilient) woman:
MR. LAUER: Let me end the interview with what is the last paragraph in your book, because I think it's stirring.
Quote: "I have said before that I do not know what the most important lesson is that I will ever teach my children, Kate, Emma Claire and Jack. I do know that when they're older and telling their own children about their grandmother, they will be able to say that she stood in the storm, and when the wind did not blow her away -- and it surely has not -- she adjusted her sails."
That's what you want them to know?
MS. EDWARDS: It is. I don't -- as I said, I don't know what the most important lesson is, but I hope it is that when bad things happen -- it's easy to get through the good days -- when bad things happen, you have the strength to face them.
Source: Transcript of Interview
I think she needs extensive therapy far more than she needs a book tour focused on her perceptions of victimhood, but it's her life to play out however she chooses. I simply have no desire to read her book.