hmmm maybe they need to be separated if thats the case. I'd be funny if she thought he was a traitor for liking you, lol. Once again she could just be really stressed and not adjusting as well as the male. I'd just work with him seeing how he's being complacent.
hmmm the nipping each other is probably normal. They've been together this long so its probably just play, but I could be wrong. I'd keep working with the male. He seems like the friendlier one. Once you get him good and trained use him to coax the female out of her shell. Their obviously attached to each other so maybe if you can convince one your now so bad the other will follow. Their still fairly new to the place and just starting to learn routines.