Part of our created humanness is that we form natural emotional and psychological attachments to people and things. But when lose them—such as in the death of a loved one—we experience the process of grief.
Despite being surrounded by people we may feel a deep sad emptiness and lack of acceptance. At its deepest spiritual level, loneliness springs from the fact that we were created with a God-shaped vacuum in our hearts and we are lonely until we find intimate companionship with Him. At the social level, we are made to love and be loved but loneliness occurs because people cannot satisfy those desires adequately. Only God can.
The story of Adam in Eden (Genesis 2, 3) shows man in a perfect relationship with God. That was part of His antidote to loneliness. But in spite of that God said it was not good for the man to be alone. Adam needed a companion like himself so God created Eve, one whom Adam could love and by whom he could be loved. When sin entered the scene, alienation from God and between the couple resulted.
God provided for restoration of intimacy with Himself through salvation, abiding in Christ, and ultimately heaven. He provided the antidote for loneliness in human relationships through friendship, marriage, family, and society.