The Good Morrow
A dude wakes up next to his lover and starts dishing about love. What the freak did we do before we were, like, in a relationship? They were either too young or too obsessed with sex, way different than what they are now: truly, maturely in love. Any previous fooling around was clearly only a prelude to this, a weaker version of the real deal.
The real deal means that this is not just about bodies; the souls are in on it too. This soulful love is so all-consuming that these lovebirds no longer need the rest of the world. They don't log on to TripAdvisor; they don't buy cheapo tickets on Kayak. Their bedroom contains the whole world.
Put another way, they are each a hemisphere and when combined in true love, they build the entire world. It's kind of like Legos. And since hemispheres are twins, or mirror-images of each other, that means that their love is so balanced and alike that it will never die. Looks like they won't be getting out of bed anytime soon!