Don't get her a semi-auto unless she plans to get training and a lot of it. In a panic situation as when under attack, working the gun mechanics, clearing a jam or just chambering a round needs to be done without hesitation and without thinking. A revolver is much more forgiving for an amateur or infrequent gun user.
A Ruger SP-101 or similar smaller .357 is a good self defense gun, IMHO. It can be loaded with .38s or .357s.
Personally, my favorite handgun is my name: Smith & Wesson model 6906: compact, 9mm semi-auto with a bobbed hammer. Great concealed carry gun but with rounds like the Hydra-Shock, it packs enough punch to qualify as a decent self-defense weapon.
Don't bother with a .380, it's too puny a round. All it'll do is piss off the crack-head attacking you, not stop him.
Actually, that looks interesting. Is that 6906 a single stack?
You echo my thoughts about the 380. And I know she can handle more gun than that if she could just fit her hands around it.
thanks.