Why do you ume my GSD was not in a good place?

Reba is resting well today and we are treating the abrasions on her mouth and nose the best we can. It isn't easy since she keeps snapping and has bitten the blood out of me twice. When I said that she sometimes scares me, I meant the way she acts around children, cats, and other animals. I wasn't afraid of what she would do to me. Maybe I should have been. Reba did not stay at an"Uncle Bubba's Shade Tree Auto Shop" in the backwoods of Hooterville. She is not a commody. I drove 1725 miles to rescue her, yes rescue for $750, and have spent a lot of money to make sure she had the best of everything. I could not stand knowing she was being kenneled all day and crated every night. She should have been a Queen as she is posted on pedigreedata.com. and she is absolutely beautiful. I wanted to give her a home with people, children and other animals to play with. I tried to keep her in my house when I first got her, but she would not stop sitting at the door and barking. I fount a male GSD that she got a long with. That male,Shift belonged to my son. The two of them played and wrestled and slept together. When I tried to take her home she would stand behind Shift or run. Shift has been on the job for 6 yrs. With 15 men around do you honestly think those dogs didn't get played with and petted every day? Reba is German Import and she is very large. I have traced her path all the way back to birth. I should have done that before I bought her, but I was so gung ho on giving her a better life and making her a pet that I didn't care where she came from. It took me 6 months to get her paperwork straighten out with AKC. I was told, and believed, she was registered. She was...at birth. I had to pay the penalties because other owners did not register her. My family said she was an obsession with me. Now I know that as hard as it is going to be, I have to let her go where she can find peace. If you think that was an easy decision...you are very wrong. I am fighting back tears just from thinking about it. I loved her as much as she would let me. I have run out of reasons for why she acts the way she does. She changes so quickly. Please learn from my heartbreaking mistake. Be very careful of rescues especially if they are older and dominent. Love can't always help them. Thank you for your time.