The people in your life that just drain you emotionally are called emotional vampires. Emotional vampires are no where near as sexy as real vampires. According to a PsychCentral article written by THERESE J. BORCHARD there are five types of emotional vampires:
Vampire 1: The Narcissist. This vampire is grandiose, self-important, attention hogging, and hungry for admiration. They are often charming and intelligent–until their guru status is threatened.
Vampire 2: The Victim. This vampire thinks the world is against them, and demands that others rescue them.
Vampire 3: The Controller. This vampire has an opinion about everything, thinks he or she knows what’s best for you, has a rigid sense of right and wrong, and needs to dominate.
Vampire 4: The Criticizer. This vampire feels qualified to judge you, belittle you, and bolster their own ego by making you feel small and ashamed.
Vampire 5: The Splitter. This vampire may treat you like their BFF one day, and then mercilessly attack you the next day when they feel like they were wronged. They are often threatening rageaholics who revel in keeping others on an emotional roller-coaster.
The article also lists strategies in dealing with these types of vampires... I normally just avoid them or cut them out of my life. I have no patience for it anymore. For the most part, I believe that all emotional vampires are narcissistic. In all situations the word revolves around them, they believe the attention is due to them or owed to them, and no not care how it makes others feel; more often than not they are unwilling to try to change their draining behaviors and do not believe they have a problem to begin with! They just keep coming to you with their problems, feeding off of you, but make no effort to change. It is like an evil merry-go-round... they keep coming to you with the same problems over and over and over; it is the same drama every day, and of course it is not their fault! Psssh... whatever....
I just say not to let other people dictate your mood. A person only has as much power over you as you let them have. I have been so much happier since I have released the emotional vampires from my life. Every now and again I will get into a draining situation, but I have learned to woosah, Om, or whatever and not let it get to me. It took me YEARS to get to this point, but I am much happier and better off since I learned how to deal with it all.
In the end just remember that no matter what someone brings upon you, Karma will take care of it in the end.