So I had this issue with my Alephena save where after I moved Elliot as a roommate (I later dismissed him and moved him in as normal) a lot of random sims were showing up and becoming roommates without my permission. I kept dismissing them and eventually figured out the problem and so the solution.

Because I'm using The Sims 3 in windowed version, it cut the bottom of my photos. Basically, follow these steps:
1. Click on Smartphone
2. 'Real Estate and Travel Services'
3. 'Roommate Services'
4. 'Disable Roommate Services'