Have you ever had those moments where you have enjoyed yourself at an event, then a day or so later you start wondering about whether it really was that good? Or alternatively, where the occasion takes on a much rosier glow in your memory than perhaps it warranted at the time? Weird isn't it? Without our realising it, the mind is at it again, unbidden, and it happens to everybody.
Strictly speaking, we cannot change that, but at least when we are aware of it and notice it happening, we can ask ourselves some pertinent questions to get to the root of what it means for us. It's a very important part of self-awareness. For example, what about those times when you've repeated a behaviour or experience and in the process started wondering why, because you suddenly remember how much you hated it last time. I would suggest that something in your memory led you to believe it was pleasureable - maybe somebody paid you a charming compliment or the ice cream was delicious - and that was what stuck with you, not the rest of the miserable proceedings!
We do it with people too, give them qualities they don't have because they did something kind on one occasion, or they make us laugh. In our minds that frequently adds up to a totality which is simply not the case and is not fair on us or them, often leading to disappointment. It's about time we acquainted ourselves with a dose of reality, otherwise we're likely to be very unhappy!