This article by by A.K. Boyle is short, simple and to the point. It is not geared towards those that have suffered a trauma, but is still a very helpful article.
We all make mistakes. It's part of the legacy of being human. Sometimes we even get so caught up in blaming ourselves for "mistakes" that we lose sight of what the past really is - a path to our present self. If you're caught up in the language and thought process of woulda, coulda, shoulda, it's time to stop!
Go easy on yourself. Offer yourself the kind of unconditional love you give others, and you'll be amazed at the healing and empowerment you'll find.
If that isn't enough reason for letting go of days (and ways) gone by, here are a few more: Forgive Yourself - Truly leave the past behind