I've been having the same resource guarding issue with Trolley. It only happens with marrow bones. She has learned to "drop it" and does so immediately if she is told to. If she growls at me, she has to immediately drop the bone & it goes in the trash. She is learning that I give good things & I can take them away. We're still working on it-I think she'll eventually get it.
Trolley did this & she is now banned from the bed when I am in it. That's MY territory & she has learned to respect that. I suggest NILIF-works wonders!
Trolley is 2. She's a very busy little girl. Fortunately she likes her crate & I've made it a safe, enjoyable place for her. She's go,go,go then sleeeeeeppppp! How about getting a lure pole?
Don't be shocked. That's about the time when they are getting very comfortable in your home & may begin to test the boundaries. I've had Trolley about the same amount of time & she has tested me twice so far....Guess who won the discussion?? You might consider reading about NILIF. It has brought us much closer & Trolley very clearly knows what is expected of her. It changes your relationship...for the better.
I'm so sorry for your loss. My father suffers from the same horrible disease. I know how you feel when you say that you are grateful that her struggle is over. With Alzheimer's disease we loose them one moment at a time. It's a very cruel disease.
I use the word "easy" & Trolley seems to understand. She takes treats very gently from my hand. I also use that word when we are rough-house playing & she gets too enthusiastic.
I did DNA testing on Nevada. She looked totally GH, but was unknown heritage. I used Metamorphix. She came back a GH/Whippett cross. Just as my Vet suspected.