main character syndrome

This is a view of the world in which you regard yourself as the main character in some filmic version of your life.  For some this is empowering, allowing them to see themselves in a more positive light and be more assertive.  For others the main character syndrome simply means that you hog the limelight and everyone else is in the supporting cast, one of the bit players, or even one of the extras, their only function being to round out elements of your story and allow you to show yourself to your full advantage.  The lights, camera, action is all about you.

 No psychologist would use this term.  They would probably stick to narcissist.  The condition has been identified in popular culture and the name given to it does capture something that we all recognise.  There is now a hashtag  #NotTheMainCharacter  adopted by those who reject this approach.