It sounds like she just hasn't had the kind of socialization she needs. You could maybe foster her for a bit and see if a little NILIF training and socialization will bring out a better personality. You might have to use a soft muzzle when working with her for a while, but she doesn't seem beyond what a little training can do by your description. If she doesn't fit in your family you could hopefully get her to a point where you can adopt her out.