we are very small compared to universe so maybe we not alone
I'm like you. I don't believe in them but we cant be alone in universe. I guess.
And you don't only contradict yourself, there is something else, if something exist, does it need you to believe in it to exist? So you are sure that we are not alone, but you don't believe in aliens? So the places you have visit, you know they exist, but you don't believe in them because you don't see them? Isn't this interesting? Belief or to be sure.
Offcourse there are living entities, even in your own body, a million living things bacterias and other organisms that are living in our body it's only logical to assume that we are defenitely not alone... and even that, Aliens probobly are somekind of breed from humans or just slightly different, I think if aliens are from humans, then aliens adapted on use of tehnology that much that their whole system has changed to be in dark clean or with dustplaces with most of the time no sunlight, but also, in the vedas,(vedas are scriptures that are even older than human history that is known, and there you have everything, how universe is created, how many human species are there(400000) and I think in human species are aliens listed too, dunno, because I don't really know that much, but I really know that, Reptile humans, nad giants, do exists and are enlisted in those human species...
And the common knowledge allready is, that aliens are running whole this planet, so if anybody would invade/destroy us it's only us humans, no alien invasion, that are just stories, aliens are more smart than just to battle with them for territory...
Also, have you every thought about how do the aliens have crafts made? on what fuel they are running or what energy?
I think, that maybe, aliens have a machine that it can fly/move in any direction with the help of sound...go on youtube type something like sound vibration levitation or how to generate heat with sound...