"Bitterness a cure for the soul"
All medicines for the body are bitter.
The same thing happens with the soul, the soul is healed through bitterness.
It is possible that in order to achieve healing of the soul one must overcome many obstacles and endure suffering.
In the case of a physical illness, there are times when the body becomes so weakened that the patient cannot even bear the bitterness of remedies. Doctors lose hope and simply abandon the patient.
Similarly, when a person falls under the influence of sin (which is the illness of the soul), they may be unable to bear the bitterness of the remedy. They may then come to believe that there is no hope left (May the Creator deliver us). But the Blessed Creator is full of love, and when He sees that the person wants to return but, due to their sins, lacks the strength to endure these bitter remedies, He takes pity on them and sets aside all their sins to save them from excessive suffering. Therefore, the Blessed Creator sends them only those sufferings they are capable of enduring.
How good and merciful is Hashem!
So you know, those "bitter" moments you go through, it's better to receive them with love, knowing that it's "a special cure for your life."
The Breslev Garden recommends: