Wow!
If she hates guns, it's going to be tough to find one that's right for her! I agree that a decent size dog would give her a sense of security. Even a small, loud dog will deter many criminals. One small breed, the Schipperke, is absolutely ferious for a little dog.
If you do buy her a gun, best off with a .22 revolver. Taurus 94, Smith 317, or Rossi Plinker are all "high capacity" revolvers that should fit her hand well. In my experience, revolvers are less intimidating, and 8(+) high velocity solid .22s will be a decent deterrent. She might even find that because a .22 doesn't have a lot blast or recoil, she's grow to enjoy shooting it.
Please stay away from the Smith 642. Don't get me wrong, they are great carry guns! I carry a Smith 442 quite a bit. But they buck and snort, even with wadcutter loads, and they can be difficult for a new shooter to use.