You seem to have a good handle on the gun-in-purse thing. It will be critical that she always stay in contact with the purse; they get left in restaurants, restrooms, cars, etc. It should have the gun in a hidden pocket where she can instantly reach it, but a snatcher who grabs it by surprise would have to look hard to find and access the .38.
The Nano I tested ran 100% reliably, was pretty accurate for its size, and due to the design of its recoil spring guide, has stand-off capability. That is, if the good guy has to ram it against the bad guy's body to shoot, it won't go out of battery and fail to fire like so many other autoloaders. Points a little low, though, and while the trigger broke in quickly on mine, it was pretty rough at the beginning.