Ask Ann Landers

In it, it says, Hanging on to resentments is letting someone you don't like live rent-free inside your head.

The phrase became widely associated with the American advice columnist Anne Landers, who used a similar version in her syndicated column in March 1990.

In short, it began as advice about letting go of resentment, and then evolved into an internet insult and the meme we know today.

I have a vague recollection of the term being used by an English politician recently, but I haven't been able to trace who it was.