Hisbodidus at night, crying to G-d and building ones good points from out of the bad, bring joy, and holds lust at bay
At night, then it is the main time for hisbodidus, that is to seclude oneself with his Creator, to express one's words before Hashem Yisburach, to converse with one’s heart to seek out the good spirit, that is, the good points that he still retains, to cull them from within the bad spirit, until he pours out his heart like water directly before the countenance of Hashem (Lamentations 2:19), and through this he will merit to joy and to quell the imagination, from which all the desires ensue. And through this he will merit memory, to always remember the World to Come, and to think at all times of his purpose and ultimate end, of the World to Come, until he merits to truthfully return to Him blessed He.
(Likutay Moharan, Torah 54; Outpouring of the Soul 60).