After trying every trick in the book (thanks, everyone, for your suggestions), one thing has FINALLY worked to stop Abbey from biting and growling at me (it had gotten to the point where I couldn't even pick her up or play with her). As suggested, I've bought a water bottle and filled it, and I keep it with me whenever I'm with her. When Abbey lunges at me to bite my hand, or starts to growl at me (this is not during playtime - this is whenever I just bend over to touch her or try to pick her up), I spray her once with water. She HATES it, and then comes back to my hand and kisses it. This happened from the first moment I used the bottle. I only ever use it on her when she tries to bite my hand, and she usually runs away now before I can spray her - she knows it's coming. I also carry it outside with us, so she'll stop nipping at my heels. This has worked like a charm - she's a different dog. She's not "afraid" of me, but just more respectful. On purpose, I pet her and play with her immediately after a spraying so she won't associate ME with punishment (just the biting). I've only had to spray her a very few times over the last few days, and she's definitely understanding the concept. Thanks to those of you who suggested it!!