Space Is Big

As the Hitchhikers Guide To The Galaxy explains:
Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the [drug store], but that's just peanuts to space.
To assure you of the veracity of the above, I submit for your edification and enlightenment, two images courtesy of NASA. If you look up on a clear dark night, you may be able to see a ghostly wisp crossing the sky - that is the center of our Galaxy, the Milky Way; just one of many galaxies in the universe. We don't really know how many galaxies, but it's at least in the hundreds of billions. There are also several hundred billion stars in our Milky Way Galaxy.

A telescope can reveal the Milky Way like this:

Now, the "milky" part is actually more stars, as you can see from the enlarged image below of a section of the first image. Starting to get the idea? And that;s just a small area of one galaxy (and ours is a pretty middling sized galaxy, best we can tell).