Is it justifiable to clean out a communal fridge?

I’m on spring break, and with this extra time I have, I decided to clean my apartment, a task that my roommates have a lot of trouble wrapping their noggins around. I have one roommate who leaves her shit all over the communal kitchen/dining room because she has absolutely no room in her bedroom. Her bed literally has a pile of shit a foot and a half high on top of it. She can barely sleep. So all the shit that she can’t fit there, she puts all over our kitchen table. I have repeatedly cleared her stuff out of the kitchen/dining room and put it in a pile in front of her bedroom door. There is enough stuff that she has to move it in order to be able to walk into her bedroom. My roommates also never do their dishes, leaving them to get old and crusty, and sometimes rot, in the sink or on the table. I go to art school, and my kitchen and bathroom are covered in paint from their projects, though I manage to do my work without getting shit everywhere. They aren’t just messy either; they are gross. There was guacamole on our floor that had probably been there for two or three weeks (I didn’t notice it before because there was stuff all over the floor). I cleaned the kitchen/dining room and our bathroom, as well as taking it upon myself to organize our pantry and fridge.

After doing all this, my roommate is pissed that I threw things out from the fridge. ROTTING things. CRUSTIFIED things. A mini jug of buttermilk that expired nearly a month ago. Petrified cookie dough and homemade icing from before winter break. Lemons that had rotted to the point where they were no longer yellow. I didn’t throw out anything that was still edible or hadn’t expired or didn’t show signs of decomposition. Is she justified in being angry at me doing this? If you were her, would you be upset that I got rid of you sour, lumpy, unusable buttermilk? Am I alone in thinking this is ridiculous?

Additionally, can you think of anyway I can keep my roommates from letting their food get to the point of decomposition when even a starving animal wouldn’t eat it? I’ve asked nicely, I’ve given reminders, and I’ve said things like “That milk is WAY past its expiration date; can we get rid of that?” but it seems that nothing is really getting through. Ideas?