That sounds really tough, I'm sorry you have to go through this, and that there isnt much that can change it. It can be nice to find a change to make but I understand sometimes its not really possible; my own room is a box room, so I'm not sharing but also sometimes I feel far too big for the house I live in. It feels constricting and like there is no where to move. Makes it tough to do what I want, especially art, cause I like to spread everything out and take up room, but my room is half filled with even a single bed. I hope university can be better suited for you. I think when it comes to holidays, you can at least know that you're going back to your own accommodation at the end of it.
Wishing you all the best for your exams, and please, rant all that you need. Like you say, you needed to get it off your chest, it can be helpful to rant about something.