Sighing: 3

In general, a person doesn't find himself in a state of bring lost. A close relationship is not replete with groans, sighs, and cries. Rather, it is built upon sweetness, peace and togetherness. But even when a person feels that way, he has the ability to connect to Hashem by sighing, which, rather than being a sign of separation and distance, is really a symbol of a relationship.
People mistakenly think that hisbodidus primarily consists of crying and screaming out to Hashem out of pain. This is because many people first adopt the approach of Breslov when they find themselves in dire straits and only Rebbe Nachman's approach seems to offer them hope.

Sighing: 2

Rebbe Nachman writes that when a person sighs he becomes a completely new person. By sighing over his wrongdoings he disconnects himself from his baser side and reconnects to holiness.

This is a result of the fact that even though he finds himself in a disconnected state, he turns to Hashem.

Many people see themselves as only able to truly be functional when they are operating at full capacity (מוחין דגדלות). They view the times when they are down as being blank spaces in their lives. It would have been better had they not even been alive. They are embarrassed by those times and wish to disassociate from them. These people are  not even connected to their own selves. They hide from others and are surely not interested in connecting to Hashem.

Rebbe Nachman is teaching that these are also times of being alive. Even then a person has the ability to connect to Hashem through crying, screaming, moaning and sighing.

Sighing: 1

Rebbe Nachman spoke often about situations which a person finds so painful to the point where he begins to cry out and moan. At times a person can bring himself to this point by calling out to Hashem and sighing. One of his students writes: I was once standing before him as he lay on his bed and said, "The main thing is ,מבטן שאול שוועתי" (From the stomach of the depths I have cried out) the words of the Navi Yonah as he was in the stomach of the fish. Rebbe Nachman explains that a person has to always grasp onto whatever he can and not give up. There is always the possibility of returning. There is never a place for despair.
If a person finds himself continuously falling into quicksand, he calls for help each time, he explained.