This morning something popped into my head that I wish I could forget. It was the memory of a bad situation which I handled poorly and have always wished that I could go back and change. But, of course, I can't change it, so now I get to be haunted by it from time to time.
Some people have pointed out that bad memories and the mistakes we make all go into the makeup of who we are. If we could go back and fix our mistakes, then we wouldn't be the same person any more. We are defined and re-defined by our experiences, good or bad, so we shouldn't seek to eliminate unpleasant things from our past... but instead try our best to learn from them so we can become a better, wiser people in the process.
It's probably true.
But don't think for a second that if there was a memory-erasing machine like they have in Eternal Sunshine of the Spotless Mind that I wouldn't have them blast out a chunk of stuff that I'd just as soon forget.
Because being haunted is nothing like they showed on Scooby-Doo.