The antonym for the phrase "sticks together" is "falls apart." When something falls apart, it means that it disintegrates or separates into smaller pieces or components. This is opposite to something that sticks together, which means that it remains united or connected as a whole. To fall apart denotes a lack of cohesion and collaboration, while to stick together highlights solidarity and teamwork. In relationships, businesses, or communities, it is crucial to stick together to achieve common goals and overcome challenges. Falling apart can lead to chaos, confusion, and failure. Therefore, we must strive to stick together in all aspects of life.