The universe is an unimaginably vast space filled with planets, stars, systems, nebulae, gas, dust -- and it's impossible for us to ever explore it all. So maybe life does exist as we do, just on the other side of the universe where we won't have the capability to find it.
Another thought: Are we putting the search for life in a box that's too neat and tidy? Should we be searching for Earth-like life at all?
All we know about life is that it must be made of amino acids, DNA, and it needs water to survive. But astrophysicist Stephen Hawking theorizes that life could exist out there that we can't even imagine: life that is not carbon-based. If that's the case, is it possible that we have already found "life" and missed it because we were wearing our "Earth" goggles?"
Either way, the quest to find life beyond this planet continues. If aliens are found, let's hope they're friendly.