Break Up Evolution

At first, of course, the breakup was the only thing I could ever think about.

Then it became like a really good (or terrible, actually) movie I saw and couldn't get out of my mind.

Then a TV show I would watch over and over.

Then an old rerun I would catch every now and then.

Then a book I would revisit because it was always open on my bedside table.

Now it's a book on a shelf.

How long until I forget the story?