[mmctaq]

If I recall correctly, you were strongly recommended to get professional help with this dog before. Did you do this?

What actual steps have you taken to socialize her with people?

Yes, Dobermans are bred for personal protection. The behavior you describe is that of a guard dog, which is not the same thing. And, not correct for a Doberman.

Are you saying that there are other dogs in your area from the same breeder/kennel or the same lines which behave like your girl?

 

[mmctaq]

To repeat: what actual steps have you taken to socialize her with people?

How often and in what circumstances does she get to interact with someone other than her immediate family? How often do these interactions result in her being disciplined for inappropriate behavior? How have you attempted to teach her that interactions with people are enjoyable?