Sick Of Me by Green Day is about feelings of self-deprecation and insecurity in a relationship. The song delves into themes of self-doubt, frustration, and the fear of being a burden to a loved one. The lyrics express a sense of vulnerability and the struggle of maintaining a relationship when one feels unworthy of their partner's love. The song captures poignant moments of inner conflict and the desire for validation while grappling with personal insecurities.