OMG, I had a BW that used to try to take my ears off, but she calmed down after a year or so. How awful about your budgie.
I have had the BW, a Blue head, and a Maxi. None were ever aggressive except the BW to me. I wonder what is making this little terror tick? Could it be jealousy or dominance?
My daughter did have a female sennie who tried to kill everything that moved except my daughter. That bird would attack my zon, the Maxi Pi, and our dogs. Female sennies are known for that, though, and pi's are not.
Keep posting and let us know if isolating helps.