Guilt and shame are big motivators to addiction. You have to let it go and move forward. It's also very important to understand that much of the ruinous thinking we experience is created by our ego, or false self, trying to protect us from being hurt but wreaking havoc in the meantime. The ego does not know time, so it may react to an event based on an emotional hurt that one experienced 20 years earlier, or even in childhood.
I highly recommend two books that delve into this - A New Earth, by Eckhart Tolle; and Awareness, by Anthony DeMello.