TheMadScientist - 6:34 pm on Feb 8, 2010 (gmt 0)
Different Data Centers...
Why would google do this to someone?
Get the idea it's someone at Google 'doing this' out of your head. Google's results (index) are displayed via heuristic and they show different versions of it (or the underlying data via Caffeine) to different people at different times.
It's been said here before and I know it's an emotional thing, but try to remove your emotions from the situation and also try to find other traffic sources so you can count Google (and other SE) traffic as a bonus. It's tough to do, but possible.
You yourself are saying the emotional ups and downs are a bad thing, but by depending so highly on Google's traffic (as it seems you do) you have put yourself in this situation, not the other way around. They run a business too and their customers are the ones who search and click on the ads, not you, so IMO your best line of defense to the emotional highs and lows is to find other traffic sources and concentrate on building those rather than worrying so much about Google.