Negative consumer behavior is an important research topic as it explores consumer behaviors that threaten a brand’s image and financial stability. However, prior research offers conflicting findings on whether a strong consumer-brand relationship hurts or protects a brand following a market disruption or brand transgression. In order to offer clarity to this issue, this work argues that disrupting the consumer-activity relationship motivates consumers to re-affirm and protect their identity thereby leading to negative consumer behavior. The data reveal that, following a brand initiated market disruption, consumers with high activity identity fusion are more likely to spread negative word-of-mouth, boycott the brand, and avoid repurchasing the brand in the future. Moreover, the data suggest that high brand identity fusion protects the brand during market disruptions; therefore, prior conflicting results may be due to the fact that the consumer-activity relationship was not accounted for. Theoretically, this work establishes that a consumer’s relationship with their consumption activities has significant impacts on consumer behavior. Brand managers and marketers are urged to develop strategies that focus on strengthening the consumer-brand relationship and not the consumer-activity relationship.