...you're an adult. It's no business of your mother's if you listen to death-metal while wanking to donkey-porn. It sounds to me like your mom is putting unreasonable restrictions on you in the hope that you'll move out, which wouldn't be a bad idea.
If it's any consolation, I've been playing Battlefront the past couple of weeks, and it's not great. It's an OK game, but extremely bare-bones with nine game modes (only three or four of which are really worth playing), and an extremely limited selection of vehicles, heroes, weapons and environments. It's quite obviously designed as an 80-dollar starter-pack to an endless stream of 50-dillar DLC's, as I'm already getting bored of the scant content now available, and they're already advertising their DLC's.