Is there any hope of Krishna’s loving protection for a falling down devotee ?

My dear Uddhava, if  My devotee has not fully conquered his senses,  he may be harassed by material desires, but because of his unflinching devotion for Me (Lord Krishna), he will not be defeated by sense gratification.

…But even though one’s senses are not fully conquered, one who has unflinching devotion forLord Krishna does not run the risk of being separated from Him.  The words  Pragalbhayabhaktya indicate a person who has great devotion for Lord Krishna, and not one who desires to commit sinful activities and chant Hare Krishna to avoid the reaction.  Because of  previous bad habits and immaturity, even a sincere devotee may be harassed by lingeringattraction to the bodily concept of life; but his unflinching devotion for Lord Krishna will act.  SrilaVisvanatha Cakravarti Thakura gives the following two examples.  A great  warrior may be struck by the weapon of his enemy, but because of his courage and strength he is not killed or defeated.  He accepts the blow and goes on to victory.  Similarly, one may contract a seriousdisease, but if he takes the proper medicine he is quickly cured.

If those who follow the impersonal system of speculation and austerity deviate even slightlyfrom their path, they fall down.  A devotee, however, even though immature, never  falls from the path of  devotional service.  Even if he displays occasional weakness, he is still considered a devotee  if his devotion to Lord Krishna is  very  strong.  As the Lord states in Bhagavad Gita (9.30) : “Even if one commits the most abominable actions, if he is engaged in devotionalservice he is to be considered saintly because  he is properly situated”. 

Srimad Bhagavatam, 11.14.18.