there is no heart that does not have clouds..

the Prophet (peace and blessings of Allaah be upon him) when he said: 

“There is no heart that does not have clouds like the clouds that cover the moon. When the cloud covers it, it is dark, and when the cloud moves away it shines.” 
Narrated by al-Tabaraani in al-Awsat, and classed as saheeh by al-Albaani. 

So the believer’s heart is sometimes covered with a cloud and its light is hidden, and it remains dark and lonely, but if he strives to increase his store of faith and seeks the help of Allaah, that cloud goes away and the light in his heart starts to shine again.