I agree with what everyone else is saying. I truely believe that the woman was wrong, and am sorry that she did that to you. I am a christian and a very big part of it to me is tolerance. It is not our place to sit in judgement of anyone.
As for the question you pose about including the period of "wildness". What is in the past is in the past. It is a part of what makes you who you are. I would probably not mention the "typical frat boy", but as others have mentioned use it in the context of what can happen when you go to college and are on your own for the first time. I would play up as much as possible how your brothers and others in the greek community helped you to find your way back.
We will be waiting to hear how everything went. I know you'll do great
