"The unexpected lesson of the post-party dream receding in wakefulness," crammed into a single-word German translation, is what it all means.
Post-party, not post-partum. Unless you insist.
Viewing/listening tip: because of the crisp timing, unless you have loads of bandwidth, let the video stream all the way in and then replay it with sound. Wear headphones and turn the volume way up. At least for the first little bit ;-)