Here’s an interesting post on Emotional Vampires. I’m not sure that I have encountered a person like this but I think the principles are important for any kind of toxic or abusive person.  Here’s a quote:

“It is important to be decisive, direct and non-reactive when dealing with emotional vampires. Remember, emotional vampires can be quite charming. Establishing boundaries early will help. But, don’t be afraid to set a new precedent with an emotional vampire, even if you know they will react negatively. Set an intention that you will not be an emotional prisoner to anyone.”

How to Deal with Emotional Vampires