Carl Sagan Explains and breaks down the Drake Equation, which will tell us the probability of us actually being alone in the galaxy, or even universe.
Many wonder what the probability means for us. We can sit and crunch numbers all we want but until we have solid evidence we can not say for sure if this really is happening. However, I think a question to ask from this would be: What if we ARE alone?
There are scientists who have crunched some numbers and theorize that the universe may be a computer simulation. If it truly is, would the lack of life be evidence for that argument? Or, if it was simply circumstance, does that leave the universe to us to explore and conquer?
We do know that there are many habitable worlds out there. If we do manage to travel space efficiently enough to visit them, even if we are alone in the universe, I think there is still plenty left to see.