BC,
I don't think you can go back to the peace you had, but you can certainly go forward towards peace. the one you had didn't last, and that, I think, is about progress as you're sober longer....you have gained some understanding and insight, and "stuff" is coming up, disturbances.
guilt, if you've done wrong, is an entirely appropriate feeling. if you didn't feel it, there would surely be something amiss.
being accountable means to me that I admit to myself and to those I harmed hat I did these things, regardless of the fact I was actively alcoholic. it was I who did them. being accountable means taking responsibility. I made amends. there are different ways of going about that, of course, and possibility of causing more harm. i found the AA steps a design to help me do that, a process to help me get to where I was willing and able, and then move on from there.
for me, it's neither about accepting that I am or was a terrible person, nor that I was controlled by my addiction and somehow now not accountable for my behaviour. it's been very much about taking responsibility for what I did and do, no matter what 'state' I was in.
righting the wrongs brings peace.