Hi Julie My first thought is a Pain issue making this girl crabby....Is she on any pain meds for the cancer?
I don't think the rawhide bone issue is uncommon...This happens at my house if all the creatures don't each have one. ;)
I would keep them seperated while your not supervising...A baby-gated room or crate for this missy while your away. (Running errands and such)....Do let her out the second you get home because socialization with the pack is very important....
Is the Maltese a female, also? This could have been a gender thing.....I have found that females are the worst!!!! I have a Bichon that will do this to only one particular Shih tzu that comes to visit...She has never done it to anyother dog, male or female! Good luck and keep us updated.....Karla
We had two female dogs, and the more dominant one would on occasion attack the smaller one. As Misfits4Me said, keep them separated when they have treats. You are a very good person to give this dog a good final home, please don't give up on her, she needs someone like you right now. Thank You.