My theory is that people who are obsessed with aliens or the paranormal are just subconsciously struggling with the cognitive dissonance they feel about the relationship between their "self" and "other" people, or vise versa.
In order to answer the question "are we alone in the universe?" first you have to establish what it would mean to be "alone".
It comes down to existential fear. "What if there are other beings out there who are more capable than us and will treat us the way we treat beings who are less capable than ourselves?"
The only way to resolve that dissonance is to believe that despite our differences with aliens, we could come to understand each other and coexist peacefully. Of course that's a difficult conclusion to come to when the people experiencing this fear generally have a hard enough time accepting the differences between members of their own fuckin' species lol