'crazy' obsessed & possessive over her boyfriend.
Will "kick your ass" if you even breath near him.
Her boyfriend is the average cheater or manwhore.
Not a normal boyfriend.
She is a crazy loon she said I can't even talk to her boyfriend.
One who is seriously crazy or deranged (needs assistance as soon as possible).
Person 1: "Wow that guy is wearing clothes..."
Person 2: "What a crazy loon!"