It's bad to be a controlling significant other.
Nancy's boyfriend Kevin has a history of being naive and getting taken advantage of by people he trusted.
Nancy wants to protect Kevin.
Nancy allows Kevin to make his own choices but tries to make her concerns known any time they arise.
Nancy tries to screen all of Kevin's friends and acquaintances, even putting a tracking device on his phone to check if he’s meeting with people she doesn't approve of.
Kevin learns from his experiences and what Nancy is telling him and is able to grow as a person.
Nancy's overprotectiveness pushes Kevin away, and he makes bad choices to spite her out of resentment.