We learn in the Talmud that since the destruction of the Beit HaMikdash (the Temple), the gates of t’filla (prayer) have been locked (Bava Metzia 59a). There are no more paths leading to heaven through t’filla. The destruction has caused a certain separation between us and Hashem.
However, this separation is only in regards to the gates of t’filla. The Sages continue to tell us that the gates of tears have never been locked. If we merit to shed tears before Hashem, our prayers will penetrate all the way to Hashem. We are, obviously, not to force our tears. If they flow fine, if not, not.
Based on Rebbe Nachman’s Soul