This is a question i ask myself every day.
It's good you said "in our galaxy" and not "in the universe" because, well, it's mathematically impossible for there not to be life elsewhere in the universe,
and as for our own galaxy goes, i like to believe yes, life can live in places that we have earlier deemed inhabitable, i'd love to delve deeper into this subject at some other time, but im a little busy at the moment and i just saw this thread and thought i wanted to make a quick reply.
Isn't it a mind blowing thing, to actually look up at the night sky, and think something out there in the universe, might also be looking up at the stars asking the exact same questions as we do, what is our purpose, are we alone? It amazes me.