How a marriage changes in character after love disappears? This can occur in many ways. For example, the couple may begin regretting the marriage after the finishing of initial love phase. Or the couple may continue together as a sense of duty with each other and begin making a life together without passionate love. That needs caring for each other.
If you look back and think of marriages few decades back, most of the couples cared for each other. They called it love. It was essentially caring. A mother cares for her children because they are her responsibility and they belong to her. Similarly, partners care for each other because they got married. This kind of thought process can take the marriage last forever. The different thought processes of I want my freedom. I made a mistake. I am not happy with you. I must search for somebody better and so on leads to break-up. This thought process is I centered, where as the earlier one I described was care centered. You are mine and I must care for you.
We have to learn to respect human beings. We have to set aside our selfish desires for some time. We have to think about destruction that takes place by frequent marriage and divorce. Developing the thought of care for each other can surely help in making a marriage last longer.