The top commenter has a good take, but it's not the only option. You can also consider taking your ball and going home. You are doing this group a favor, and you have every right to just now out of being their DM. A game isn't a classroom or board meeting, and you don't have to fight to manage the group or earn their respect. You are being treated like a substitute teacher, but you have a reasonable expectation that your boyfriend's roommates won't act like middle schoolers.

Even if you do chose to go the more difficult route, just remember that you are being generous with your time and energy. If the players don't reciprocate with their attention, just walk away.