I hope to expand on this spiritual problem, which I have called by different names.  Basically these people are hard hearted like Pharaoh in the Old Testament.  They have no empathy for anyone and use everyone for their own ends, whatever that may be.  And when they are through with you, they will happily throw you away.  With one such person I noted to them that I felt like I was a necessary evil.  When I was no longer necessary, all that was left was evil, and thus they threw me away.  These people can be persuasive.  However, when you cross them, and you will, you feel like you have been dealing with a porcupine.  I am still pulling the quills out from the various people I have dealt with. 
The Sociopath Next Door
    This came to light and finally brought together information from Pope Saint Gregory the Great's Rregula Pastoralis, The Name of the Game Is Shame and Control Freak.  I have dealt with a number of people, who have sociopathic tendencies.  I will name one, and that is Teresa Benns.  The others may recognize themselves from the statements I make on this website.  If you do a search, there is not a great deal of information on sociopathy.  And when we think of sociopathy, we think of Jim Jones or Ted Bundy, and yet these are only the more egrious members.  According to this book, one out of every twenty-five Americans is a sociopath.  This is defined as having no conscience in the book, although I think that this is a deeper spiritual problem, as I read in Saint Gregory the Great and elsewhere.  These people will do anything they think they can get away with.  The only restraint they apparently recognize is punishment.  And so most will stop at violating the law to the point of being incarcerated, although a few will even flaunt the law.  If you have ever dealt with someone that made you feel like you have been used or have gone beyond your own moral beliefs, because of their persuasion, I recommend reading this book.