Depression Prevents Hisbodedute

When a person is happy the entire day, it becomes very easy for him to dedicate an hour where he can break his heart and in front of Hashem. However when a person is sad and depressed, heaven forbid, then it is very difficult for him to do Hisbodedute and talk to Hashem.
(Sichos Haran 20)

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Tzadik Yesod Olam
Rebbe Nachman of Breslov on Shmiras Habris