Carl Sagan wrote something in Cosmos that really blew my mind. He said there are roughly 10,000 stars visible on a clear night to the naked eye. A handful of sand holds roughly 10,000 grains. There are more stars in the universe than individual grains of sand on every beach and desert on the planet.
Yes, the universe is that big!
I have no doubt that uncountable other planets have life, even intelligent life. Many of them have probably mastered intergalactic space travel at sub-light speeds. They just don't know we're here. If they had telescopes that could detect made-made objects, geometric shapes and such, they wouldn't see them if they were more than 4,000 light years away. If they were looking for radio signals, that lowers it to about a mere 80 or so light years away.
Good points. Light speed communication is basically new to the people of our planet.