An analysis of relationships

Why is it that people are so sentimental? I cannot understand why emotions govern people, driving them to do things they are otherwise incapable of! People who are emotionally driven do not have much concern for the consequences their actions may cause. Thus in a storm of passion actions which seem ruinous afterwards are committed without the slightest remorse. Sometimes I wonder how people in relationships can bear the devastating impact of their conflicts. I guess it comes down to this, every relationship is built up of a series of transactions. The survival of the relationship depends on our ability to keep a positive balance in these transactions. Once the deficit reaches a critical point, people drift apart to such an extent that nothing can bring them back again. .