rant: my flatmate is awful!

Her boyfriend basically lives here without contributing to any bills and yesterday night it was the tipping point. They came home drunk with friends at 2,30 in the morning, knowing that I had school at 9 and that we have a rule of no noise after midnight or so.
They barged in and chatted so loudly for the longest time right in front of my room when the light was off and I was clearly sleeping. 
And a few days ago she had the nerve to tell me off because at almost midnight I had some music in in the kitchen while doing the dishes even if I checked that they were awake with the lights on in the room and because I heard them chatting. I'm so fuckin done!!!
  With what courage she tells me I'm a bitch for setting up some rules to live happily together when she's so inconsiderate?