RE: When an FBI agent comes in contact with someone’s mind altering dark side, she must make to tough decision to kill him and end the monster’s destructive ways or face the consequences of her actions of letting him live.
Making a decision describes a scene. A logline describes a plot.
What is the plot about?
Does the psychic kill someone and the FBI agent is tasked with tracking the bad guy down; and the story ends with the confrontation described in your logline?
Does the story begin when she comes in contact with the psychic and the story is about the consequences of her letting him live and what she must do about it?
In other words, does the scene in your logline describe your inciting incident or does it describe the climax?