We all are. Like rats in a box.
We don't actually need planets to live in outer space. Think about it: If we can build starships that take 1000 years to get anywere, we will have essentially built our own worlds. Don't need planets, it's a lame excuse for staying on this backwater mudhole of a planet.
OTOH, I'd also like to see a few other worlds. Unfortunately, it's just too darn expensive to get there.
I've read the asteroid belt has enough material to construct the equivalent of 1000 earths, if we make them hollow, live on the inside, and produce a simulated gravity through rotation.