We all have to realise that we're dealing with human beings... and human beings aren't really outstandingly honest with themselves let alone other people when it comes to their emotions.
I know, I know, that's all so easy for me to write and as glib as you like, but you're suffering here, and what kind of useful advice can I give?
You write: "he was told that she was uncomfortable because she didn't know me as well as she would like. She and I talked and that was clearly not the case". Does she like you? Do you get on generally? If so, why not spend some time with her, work on that relationship, build up some trust? If your reaction is "I can't spare the time", consider that she might feel "I can't spare my husband".
In any case, this is going to need patience. That doesn't mean sitting around doing nothing, waiting for her to change her attitude. It does mean don't expect her attitude to change very quickly.
I wish the best for all of you. Keep us posted...