I've never really felt those "wow I didn't realize it was that far back" moments, maybe I'm just good at keeping track of time.
Except it's really freaky that wife and I have been together for 10+ years. I remember both of us feeling like battlescarred veterans of life at that point. Oh how young we were... (Although to be fair, life has been better=easier in many ways since.)
However, I re-entered the Helsinki university 10+ years after the last time, and while I don't actually feel that different from the younglings in general (and mostly they are pretty shocked to hear how much older I am, which I take as a compliment), I feel ancient when sometimes every other thing I say refers to events and things that happened when the kids around me were, well, smaller kids
Propably the one thing that sort of weirds me out is this, as it touches close to my heart.
In the early nineties, which was propably the last time this situation existed, peopl who were seriously into rock could and often would know more or less all the classics starting from the sixties (at least by name) and have an opinion on most bands that were even remotely commercially significant at that time. There really weren't that many. There was a store in Helsinki about the size of my bedroom that had pretty much everything you needed to reach that level of knowledge and plenty more. That common ground is now unreachable, there is just too much going on all the time and even the sphere of classics has grown huge. This point was actually reached quite some time ago, but I still find it an odd how we've reached a point of no-return in that.
The Rock Police with All The Right Opinions are replaced with hipsters who mostly just talk out of their butts and don't actually know much anything.
Also, albums seem to be a bit of an fuzzy concept to kids these days. It's bands and songs that matter, not albums.