It is not possible to answer a question like this without access to eternity and infinity. But if I had to venture a guess, I would say that it seems unlikely that we are alone in the universe.
However, I would also like to point out that I may be finding this unlikely simply because we humans have an in-built need to see our likeness reflected in the universe.
It is often suggested that the universe is so vast that the possibility of life not existing elsewhere seems like a waste of space. But upon a little reflection, we might find that that sentiment stems from our regard for ourselves.
We think the absence of life is a waste of space because we think life is valuable. And we think life is valuable because we are alive.
But what if a lifeless universe is not a waste of space? What if life is an isolated event, a cosmic accident that happened on our measly little planet somehow and nowhere else? What if we, convinced of our value on this little planet, are actually alone? What if we are the waste of space? What if, by some objective standard that we will never have access to because we are alive, the phenomenon that we call “life” is an aberration — a hole in an otherwise perfectly sterile cosmos?
Just something to think about. Being alive is nice. Hoping that there are others like us out there is also nice. But we have to also keep our eyes open to the reasons behind why we think this is nice.
I made a tiny video version of this answer over on my YouTube channel. Subscribe!