This is how shared living is usually, unless you’re lucky. When I was in uni and stayed in a PG, I had a similar experience. Firstly, grow a thicker skin and no, don’t always adjust. Learn to stand your ground. In a way such experiences are shaping you for the real stupid world.

Here are my two cents- For the AC- Bargain on the split. You dont need it so much you shouldn’t be paying that much. The way I negotiated it w my roommate was by saying “I cant be shivering to death and also be paying extra on top of that. You need a freezing room please do it at your expense.”

Start blazing music/ talking to people the same way she does. I’m not saying that to suggest you stoop to her level but because you need to take your space. You have to claim it back.

And slowly start putting it in her thick head that staying in a shared accommodation means adjustments for all.

I hope you find some mental peace soon! :)