It says in this week's Parsha that the malachim said to Lot: "Escape with your life. Run away and DON'T LOOK BACK." Lot's wife looked back and turned into a pillar of salt.
When escaping from the Yetzer Hara, we dare not look back. Feeling guilt and shame from the past is often the greatest cause of our inability to move forward. We must decide to escape SEDOM NOW and never look back. The past is out of our hands and must be considered as if it was Hashem's will -as if we were born this moment with all the memories of the past implanted into our brains by Hashem, so that we can deal with our specific tikkun and situation. But we can never to allow those memories to weigh us down or prevent our progress! All we have is NOW. The past is out of our hands. Don't look back!!