This question involves many fields such as psychology and film culture. The following are the possible answers: Fear and entertainment: Although his girlfriend can't sleep when she sees something she's afraid of, watching horror movies is her way of entertainment. In the movie, she might feel a certain sense of security and belonging, which was in contrast to her uneasiness in life. 2. Fear and challenge: Girlfriends may think that facing what they are afraid of is a challenge. They can avoid this challenge by watching horror movies. This method might make her feel safer and more comfortable. Fear and self-defense: Your girlfriend may have experienced some unsafe experiences in certain situations, making her very sensitive to fear. Watching horror movies in this situation could be her self-defense mechanism to protect herself from further harm. It should be pointed out that everyone's fear and entertainment are unique and should not be used to measure or criticize each other. Only by understanding her fears and entertainment methods and respecting her preferences and choices could he better communicate with her.