Regarding the weight in a purse (someone above said that weight shouldn't be an issue if she carries in a purse,) I actually gave my fiancee a Surefire G2 flashlight, and she later reported that she didn't like the fact that it added extra weight to her purse(!) Probably something to do with how weirdly small the straps are. (What do I know? Never carried one myself...) I would suggest that a polymer frame would be the best way to go. I'm personally a fan of the Kahr, and would suggest a PM9 (due to its very small size/weight,) or the CW9 (if she doesn't like the small handle on the PM, and b/c it's relatively less expensive.)
I personally didn't like how the Kel-Tec felt in my hand, and especially didn't like the trigger pull. But that's a personal taste thing.
Of course, she needs to go to the store and check all this out herself.