Someone defined "insanity" as doing the same thing repeatedly and expecting different results. If you try that in Google, you might actually get those different results - but don't worry, it's not you!
A few days ago we blogged about the need for titles on web pages, and while doing so, we searched for a handful of different phrases to find the most illustrative example for our screen shots.
First we searched for "health insurance frisco tx" and then "physical therapy frisco tx" before finding what we wanted when searching for "pizza frisco tx."
On the third search, we saw Google results that included items from the previous searches, totally unrelated to "pizza." See the screen shot at the right.
(The screen shot was fortunate, because trying to replicate this several times resulted in a different set of links each time.)
So no, you are not losing touch with reality -- Google really does vary its results on one search based on what you searched for previously.
This means that your results will vary from one search to another even on the same topic, and if you are on the phone with someone telling them to Google something, their results might very well vary from yours, even at the same time.