To the degree we forget Krsna and Srila Prabhupada, to that degree we feel lonely. Even after receiving and sustaining in our MIND the information about Their presence, our HEART may still not be satisfied due to lack of active relationship to the Supreme Lord and His pure representative. This relationship can be only reactivated by active devotional service, service to the mission of Srila Prabhupada.
As our heart is not completely filled with love of Godhead and love for His pure devotee, a vacuum so created establishes a need to be fulfilled elsewhere.
This leads even after many years of practicing “theoretical Krsna consciousness” to falldown as the feeling of loneliness becomes more and more intolerable. After all, the nature of the soul is never to be alone.
Strong association with devotees, godbrothers, is great help as much as sadhana and intense hearing from Srila Prabhupada who can be found in His books and recordings. It is also necessary to be properly situated within ones varna and asrama.
This world is a world of lonely people and no amount of pathetic proclamations of love and brotherhood will change it. Unless we don’t unite with the Supreme, we will not be united. Loneliness means artificial separation from the Supreme Lord. As proven by those who are indeed engaged in Srila Prabhupada’s mission, they have no problem to find friends engaged in the same fashion. They have no problem with loneliness.