If you look at just our local solar system there seems only a very slight chance that anyplace but Earth has any life potential and the nearest star is around four light years away so that, unless some extraordinary method of travel is discovered it is unlikely much travel can take place. Star Wars and Star Trek are unlikely science fantasies. But considering our local life there is no intelligence comparable to human other than human so intelligence, even under the best of conditions, intelligence does not seem to develop easily. And even close intellects like the chimpanzees and perhaps dolphins seem extremely unlikely as intellectual companions as no easy communication to them has been discovered. There is, of course, the slight possibility that other intelligent Earth life is well aware of the brutality and destructive tendencies of humanity and are keeping themselves well hidden, but I doubt it.
There are innumerable stars with planetary possibilities in our own and other galaxies but even communication at light speed makes contact too cumbersome and unlikely considering the time lag. Nevertheless it is probably wise to keep listening and keep trying but I wouldn't bother to worry about little grey people.