Well, I also had lots of flashbacks, though not of my blackout periods. The blackouts are lost to me forever and that's scary. I think that the flashbacks will not stop as soon as you detox, but as your life changes, they will likely lessen. The thing is, when we drink we numb our feelings away. When we stop drinking, all those feelings that we've hidden from are still there and we still have to deal with them. Try to focus on positive thoughts and feelings as much as you can.