Mom's new roommate has full-time aides and it's affecting mom negatively. Any suggestions?

Moms is in late stages of ALZ but still highly functioning in many areas, she just got a new roommate who is an invalid and has full-time aides; this lady moans, spit across the room, hits and screams 24/7. My mom is normally all smiles and happy go lucky. Not any more; she's crying daily, she doesn't understand all the noise, isn't getting any sleep and is a stark contrast to who she was the day before this lady moved in. I understand there's an adjustment period but is this normal procedure to 1. have a patient share a room with someone at the other end of the spectrum? 2. have a patient requiring 24/7 aides to share a room with my mom? and shouldn't they be paying 2/3 of the rent then since there's 3 people in the room 24/7? I understand the lady needs care but, I feel like it's to my mom's detriment; I had her at my house 8 hours yesterday and she didn't want to go back to the MCF. My mom has never done this before. Any suggestions on how to address this?