Thanks for the good thoughts, everyone. I'll keep looking for her, and I'll keep looking at the shelter to see if animal control comes across her. I've heard of people who have had their cats missing for 6 months and gotten them back. Sweetie's been missing for just about 6 months now, but maybe she'll still show up. My brother, mother, and I will be looking for another place soon so we won't have to deal with her roommate anymore and my brother and I can get away from our father.