Travel to the side of the earth that the moon will impact (cause you sure as hell don't wanna live on an earth with no moon, plus it would look pretty awesome to see a flaming moon coming down) and do what pretty much every single person would be doing in the event of an inescapable apocalypse: Screw, screw, screw, and screw by the "Moonlight". Search your feelings, you know that once people know shit is gonna hit the fan, all taboos and societal norms will be thrown out the window. There will be no reason for you and say, someone you've been having a sort of sexual tension filled relationship to not just up and go down on each other with no consequences in sight. Angry parents? No tomorrow. She's pregnant? No morning after. STD? Gonna die anyways. Same goes for drugs for pretty much the same reasons.
Just so everyone knows, I'm NOT talking about rape. Shit be bad. Though there would probably be some sick bastards doing it.