We seek happiness by stimulating the senses and the mind. No matter how much stimulation we get, it leaves us empty. There is a great difference between pleasure in the body and the mind and real happiness. No material experience can truly touch us in our hearts. This is a realization that the experiences in this world cannot satisfy us completely.
The craving for happiness is a spiritual longing. We need spiritual food. If we have unrealistic expectations of materialistic relationships, of anything in this material world, thinking that these will make us happy, at some point you will become profoundly unhappy and depressed. This material world cannot deliver what you seek.

A mindful person will know what their goal of this human journey is. As we said earlier, just living for passing material pleasures will not give us what we are looking for. As long as we identify as being material, we will be pursuing temporary, passing goals. This brings us to the question what is our real function? Since we concluded that we are eternal spiritual beings, then we should also have an eternal function. So, what is our eternal function? It is to render loving service and not live a self-centered life. The nature of the soul is to serve, not to be served. A connection of loving service to the Supreme Soul and to others. This is our real eternal function and purpose. When we are acting on our true function and we try to offer everything we do to the Supreme Lord, then we will automatically experience real lasting happiness.