I surely believe that in our huge universe there are other civilizations - thinking that we are alone in the universe is as stupid as to believe that the Earth is located on a turtle.
We are all entitled to an opinion, popular or not. As mentioned, it does not change the facts and whether or not something is true.
Calling someone stupid is not a point of argument. SO, Instead, consider this from a purely logical perspective.
Lets raise the question; Whether we are or are not alone, where did the original matter come from in the first place? Assuming a point of origin for the universe or not. The matter and/or energy had to come from somewhere.
All matter and energy tend toward a state of equilibrium. The fact that it hasn't yet been reached, means there was a start. It also means that the amount of time which has past in a universal sense is not so great that there is virtually no activity.
This is the basis of this argument with Stephen Hawkins:
So, by this definition there Is an "alien" source of the universe, ie: lt wasn't man.
But it probably isn't what you had in mind