I have never been very good at grey either Bounced.
There are always other markers...90 days, 6 months...
I found that really depressing early on though because I couldn't imagine getting that far and I guess I hadn't accepted myself as a non drinker either. That is a constant work in process in a way.
It becomes easier as the days pass not to drink but then the further away you are from your last drunk then the easier it is to forget the reasons why you quit in the first place. I know that 'Thinking the drink through' certainly required more effort as time passed.
I second Seanie's suggestion of AVRT. And BBThumper's suggestion of AA...
Well done for recognising this as a danger point, now you just need to find the right tools to get you through it x