What does it mean "mess with your head" in this context? Kevin: Family. (sighs) It can mess with your head, can't it? Patrick: Yeah. Kevin: Whenever I go home, I just regress to being 14 again.(he's thirtysomething) I stay in my room, sulking, playing Tetris. What does it mean "mess with your head" in this context? Does that mean family can hurt or upset you sometimes? Thanks in advance for your help!