I've noticed that whenever I've been engrossed in something for a substantial period of time and it abruptly ends (such as books, video games, or television seasons on DVD), I get this horrible feeling that seems like it might be similar to post-partum depression. For a couple of days, I feel empty, and all I can think about is that one thing. Eventually, it fades away, and I'm back to my usual self. Does anyone know if there's there a name for this? I'd like to read about it.