Statistically, every possibility is equal. Life happened once and given enough time, it's a mathematical fact that it will happen again. It seems unlikely to us because we are looking at it from the wrong perspective. All we can see from our point in the universe is places where there isn't life right now. That means absolutely nothing. It's the same as an infant believing that objects do not exist when they don't see them. Our technology is still so limited, we can't even begin to really say what is or isn't likely outside our planet.
The idea that other life forms couldn't exist in certain conditions seems very ignorant to me. All we know is what we've learned from 1 case study. Imagine a psychologist saying that because 1 person has traits a b and c but not d or e , its impossible that anyone else to have traits d or e and people can't exist without a, b, and c. They'd be run out of the profession! The scientific equivilant shouldn't be taken as absolute fact.
On the personal side, I love the idea that somewhere in the universe there is life. It's incredibly unlikely that we'll find it in my lifetime so I can meet them but I can dream

I haven't read much about the UFO accounts, eyewitness accounts, etc but the subject is fascinating.
If you ask Stephen Hawking or Albert Einstein, the universe is finite. Whether is truly is or whether there are other factors we don't know affecting their calculations, who knows.