Okay, so, update time. Sid and Nancy lived apart for 2 weeks. In that time, at first everything was new and exciting, and the first few days they enjoyed exploring their new, separate homes. After the novelty of everything wore off, they both slowed down a super lot. Nancy wouldn't leave her igloo for anything, not to even run on a wheel, and Sid retreated to the back corner of his cage, where he would lay there all day and refuse to move. Both of them stopped eating. I began to panic. I decided to let them have a supervised play time, and both of them perked up so much, it broke my heart. Nancy ran to Sid and crawled underneath him, Sid groomed her all over and curled his whole body around her. I let them interact for an hour, before separating them, thinking maybe I'd just let them have supervised play times daily. When I took Nancy away, Sid went nuts. He started tearing apart his cage, digging up the fleece and flipping everything over, sniffing everywhere. He was obviously looking for her. Nancy retreated back to her igloo and refused to come out again. After an hour, Sid gave up, went back to his corner, and laid back down, and continued to refuse to eat until the next day, when I let Nancy visit him again. This time they both went into his house, and he pushed his fleece scraps in front of the opening, I think to try and keep me out. They stayed in there for a half hour, and just slept, cuddled up together (It's a transparent purple plastic igloo, I could see them inside) Afterwards, Sid came out, grabbed a ping pong ball, a jingly cat ball, and a few pieces of food, and tucked them in there with Nancy, then pushed the fleece back inside of the door way. He sat outside the igloo and stared at me. I think he knew I was going to be taking her away soon, and he was trying to stop me. I pet his ears, and he relaxed a bit, but tensed every time I tried to touch the igloo. He wasn't being aggressive, just obviously upset.
I decided separating them wasn't working. Since they've been back together, they've been doing so much better. They do literally everything together. They eat at the same time, play together (Sid is really gentle with her, it's endearing), groom themselves at the same time (Then Nancy grooms Sid's back for him, since he can't reach) and sleep together. If Nancy gets nervous, she runs to Sid, and he protects her. Since they've been together, Nancy has been running on her wheel again, and exploring, instead of shutting herself in her igloo. Both of them have started to trust me more, if Nancy sees Sid sniffing my fingers, she comes over and checks me out too. If Sid crawls up my arm, so does Nancy. I think he's going to help her get better associated with me.
After witnessing how attached they are, I don't think it's fair to try and keep them apart. I know some of you are going to think I'm making a bad decision, but I can't let them suffer like that, they were seriously dying of heart break. It's an odd situation, and I would never, ever condone putting a rat and mouse together, but these two seem to be an exception to the rule.
Here are a few pictures of them together.