If you can't beat 'em, hit them in the face repeatedly with a pick axe while weeping and then build a giant wall to make sure they never get close to you ever, ever again.
Steam user Maximum Player offers a pretty spot-on rendition of what I (or any of you) would do if we woke up in Five Nights at Freddy's and suddenly had Minecraft powers. Admittedly, I would probably screamcry more tears of my own blood while plunging my pick axe into everything that moves, but the outcome would be essentially the same. And then walls. Walls everywhere. Double-wall, triple-wall, infini-wall over every possible entrance.
Or maybe I'd just tunnel out and build a cool fortress that looks kinda like a shark if you squint. But then walls. Walls over every door. Just to be safe.