This paper critically examines the interrelated roles of attachment styles, communication patterns, and conflict resolution strategies in sustaining long-term marital relationships. In a socio-cultural landscape where marital instability and divorce rates are rising, understanding the psychological and interpersonal foundations of enduring relationships is both timely and essential. Drawing from established psychological theories including Attachment Theory, Systems Theory, and the Gottman Model of marital interaction, the paper argues that these three dimensions form the core pillars of relational durability. Attachment styles, developed in early life and carried into adulthood, profoundly influence emotional security and relational behavior. Secure attachment tends to foster trust and resilience, while insecure patterns (anxious, avoidant, or disorganized) often undermine marital stability. Communication patterns, whether constructive or destructive, shape the day-to-day dynamics of the relationship, serving as either a conduit for intimacy or a trigger for misunderstanding. Conflict resolution strategies, meanwhile, determine how couples navigate inevitable disagreements, with adaptive strategies (compromise, empathy) promoting cohesion and maladaptive ones (avoidance, aggression) escalating relational distress. This paper adopts a desk-based approach, synthesizing empirical findings and theoretical models to assert that long-term marital success depends not on compatibility alone, but on the conscious cultivation of secure attachment behaviors, effective communication, and emotionally intelligent conflict resolution. The paper calls for a shift in marital counselling, premarital education, and relationship support programs to prioritize these three dimensions as central tools for relational sustainability.