Final answer:
Christie's constant thoughts about a man she met suggest she is experiencing limerence, which involves intense, involuntary feelings of romantic desire and attachment.
Step-by-step explanation:
Christie is experiencing limerence. Limerence is a state of mind resulting from a romantic attraction to another person which includes obsessive thoughts and fantasies, and a desire to form or maintain a relationship with the object of love and have one's feelings reciprocated. Christie's constant thinking about the man she met indicates that she's going through the intense and involuntary psychological state of limerence, rather than a fatal attraction, hallucinations, or simple lust.