When I was younger I was like there isn't life on another planet, but that was because I didn't no how big the universe actually is, and I still don't, but I know it is bigger than what I thought then. I used to think that space ended at Pluto just because of it being the last planet that's 'close' to us. The universe, to our understanding, is endless, meaning that there are more planets that we can imagine. No-one can tell me that on one of those planets there isn't something that is living. It's just not possible for Earth to be the only planet that has living 'things'. Maybe they're not near us, but they're there somewhere.
Do I think that we will ever find out? No.
It has been, is, and will always be a mystery.