Insanity: doing something over and over again and expecting different results!

How come when things are over, all you can remember is the good things?
Is that why we return to old lovers? stay in jobs that we complain about? re-live the glory days of our high school years?
In thinking of a former relationship, and wondering how he is doing, why am I not able to think of the end? It was final, infinitely final. What he said to me would not encourage/entice any "ex" to ever call him again. He made that very simple. So, why do I still miss him?
It has been easy not to call. I remember the words, I replay them in my head. Generally this is enough to discourage me even before I go to the phone. However, I made it to looking up his phone number the other day.
Oddly, what stopped me then was I realized that I still had no real reason to call.
And he hasn't.
So, that is the answer.