Newatthis,
You are correct about time counting being beast activity, but your dilemma comes from trying not to think about how long it has been. The more you try not to think of it, the less you will succeed. The Beast is locked onto that last drink date like a hungry dog on a delicious, mouth watering meatball, so it is unlikely that you will forget the date. It will also try to create a sense of amazement - "WOW!!! It's been soooo loooong since we had a drink!!!" says the Beast.
The length of time since last drink is ultimately meaningless in the context of permanent abstinence, unless, of course, you think you are between drinks, in which case new daily records do mean something. In AVRT, we simply let the Beast do the counting (it can't resist), and just recognize it as any other form of AV. The next time you have thoughts of how long it’s been, just recognize it as AV, as your impatient, powerless Beast, and relax while it struggles futilely.
As for telling others about your Big Plan, that is up to you. Personally, I'm not keen on broadcasting problems, and outside of recovery forums, my response is usually "no, I'm not drinking" or "I don't drink." You don't need to be afraid of telling people that you've quit, but what you do need to be aware of is your reason for telling people.
Are you telling people about your BP because you want to be "held accountable," and have them look over your shoulder, which implies that you don't really mean it when you say you've quit? If so, then that is AV. Otherwise, if you think they have good reason to know -- and some in your inner circle may -- then there is no problem.