Teshuvah Lives in the Heart
Asked how far a person must afflict himself to repair a wrong, the Noda BiYehuda answered that fasting is secondary and that the heart of teshuvah is turning back to Hashem.
In a long responsum on teshuvah, Rav Yechezkel considered the system of penances measured to the weight of each sin, as described by the Rokeach. He then set out what he held to be the center of the matter. Fasting is only secondary to teshuvah. Its essence is to leave the sin, to confess with a broken heart, to feel sincere regret, and to draw close to the Creator with warmth and love. To return to Hashem means to cling to Him. Fasts and harsh self-denial are not the root. He pointed to the Torah, the Prophets and the Talmud, which promise that one who turns from wrongdoing is fully forgiven, and he reasoned that if the heavy measuring of penance were the essence, such promises could not stand. The deeper question is whether the person has truly returned.
Source: Noda BiYehudah, Mahadura Kama, Orach Chaim 35
If you have fallen short, whether with a person or in your avodah, do not let guilt turn into a show of self-punishment. Ask what real return looks like. Stop what needs stopping, say plainly to Hashem and, where it applies, to the person involved what happened, and mean your regret. Then take one small step toward closeness, such as a few minutes of honest davening or a call to make peace today. A heart that has truly turned is worth more than any display of severity.