My group leader in the Recovery Home talked about lost/missing memories. He blamed it on the extreme selfishness that we were in at the time. The "present moment" didn't mean much to us as we were constantly in the past or the future.
I find as time goes along in sobriety that a lot of lost memories come to the surface. I always say "Thank you, God" when one appears.
Bruno, are you going to AA?
All the best.
Bob R