I think in a way its good you're worrying about this. It shows you really don't want to relapse
I have large gaps too - I still can't remember too much of 1996-98...but I have more than enough other memories for me to stay sober. I'm sure you do too
In fact when you think about it the fact we have large gaps in our memory and we can't remember is a pretty good reason on its own never to pick up a drink again?
relapse is NOT mandatory.
Use the support here and do everything in your power now never to take another drink.
D