I adopted a dog exactly like this. Lots of love and patience. Take things at your dog's pace, not yours. Try to walk her at night so she can get used to her surroundings when it's quiet, and gradually switch to daytime. Don't go to her, let her come to you so she doesn't feel scared or threatened. I even went as far as to not make eye contact in the beginning.
I strongly suggest you read the website below thoroughly. Debbie Jacobs literally changed Iker's and my lives. Her Skype course is great, as is her book. You'll gain more understanding and acceptance. Please urge your husband to read it, too.
When she does come around, and she will, they will be the best moments ever.
http://fearfuldogs.com/
Edited to add that different dogs have different personalities, just like we do. Just because she has fear issues doesn't mean she's not a good fit at all. I would have been heartbroken if anybody had told me that Iker wasn't a good fit. We're a great fit, so don't let this discourage you.