Our experience of this world has taught us that there is no real happiness in material objects. Initially, we may derive a lot of pleasure, but with time, happiness disappears. We might have embraced our dear ones - mother, father, son, daughter, husband or wife thousands of times and cherished our favorite Indian sweet - rasgulla thousands of times, but we still remain tensed and disturbed. We have not achieved eternal peace or happiness from any of them. Our ultimate goal is to find happiness but our experience seems to be the opposite.
Pleasures related to the senses are present in this material world as well as in heaven. It is a myth of this material world that we get immense happiness. After the initial pleasure, it keeps decreasing with time and finally turns to sadness. For example, on the arrival of a newlywed bride, we dance, sing and spend lots of money. Extra care is taken for her. But after a few days or weeks of association, we tend to be disappointed with her. We think that, "may be the other bride is good ; the others person's wife is better".
Everybody wants his / her own happiness. The way you expect to get happiness from your wife, similarly, even your wife expects to get happiness from you. It is very obvious that there will be a conflict since both are fooling each other to get happiness, but none of them have it. Both say that they wish for happiness to the other. But in reality no one wants the happiness of the other.
We think that the attainment of a material object or a person will make us happy. But when we get it, we no longer derive happiness from it. We get disturbed because that object no longer provides the same level of happiness as before. We have all experienced this before, across countless lifetimes. It is the intellect that must decide that the material world has been created for the body, and not to provide happiness for the soul.