There is a tendency for people who have made choices and have done things that they are not proud of, to have very negative feelings about themselves. They may feel that even if they now have gotten their act together and they are upstanding human beings that they are still tainted in some way.
The Rambam in chapter seven of the laws of repentance, says that nothing could be further from the truth. In fact, Maimonides writes that there is a special place for the “Baal Teshuva”, the repentant one. Yesterday he was despised and distant from G-d and today is close and cherished by his Creator. The Rabbis say that the place where the Baal Teshuva stands even a righteous person his whole life, cannot stand. Such a person has tasted sin and now has acquired the courage to overcome his temptations. G-d fully understands the struggles towards making the correct decisions that one goes through.
The Yom Kippur message is that regardless of how low a person may have fallen, there is always the opportunity of repentance. And, if one is able to return towards that which is right and holy, he will be embraced by the Al-mighty with intense love and affection. Gmar Chatima Tova.