I have a sister that is exactly as you describe you mom (and as EG has been described). She has two children. She had multiple CPS cases against her when her children were younger. She was a filthy house keeper when they were growing up. She no longer has communication with one of her daughters, and the lack of communication is at the fault of the daughter...as she portrays it to anyone who will listen. My sister is thought to be narcissist with borderline personality disorder. She is physically and emotionally abusive to our parents, her grandchildren and us - her siblings. We, the siblings, have all distanced ourselves from her, her lies and manipulation. Extended family tend to still fall prey, and even one of her daughters gets sucked into her cycles of use you/hate you.
I have found by watching my sister over the years that there are only two types of people that are willingly around her "on purpose". Type 1 (Her husband) those with no self esteem, that are broke down and don't know that they deserve better, and will willingly go along with her ploys and evilness just to make her quite down for a moment. Never catching on that it doesn't work. Type 2 (my nephew) other narcissists. They play off of each others dark side. She tells him she hates someone, he sneaks over and kills their dog (true story). Together they not good. She is a mother figure to him, in a non-nurturing way. They are two evils in a pod!
Only giving my sisters story to say that I think it's highly possibly that EG is a narcissist that will deny whatever she did until her last breath, but it's also highly likely she had someone familial with a similar personality trait that fed off of her and would have helped do anything, no questions asked, and like PB said - others know after the fact. My sister & nephew have a small circle of people they talk about their activities with.
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