380 is a good caliber for a female. Only thing I would've done different is got a compact one, something like the M&P Shield 380 that she could also carry in her purse. I know people talk about stopping power a lot, but trust me, a well placed shot with a 380 and aint nobody gonna keep coming at you. FYI the caliber that causes the most deaths in the US is 22.
380 or 9mm is a good concealed carry caliber. It's not about "stopping power" with 9mm, .40, or .45. Most people survive most gunshot wounds, period. They come in the ER ALL THE TIME and are walking out in a couple days. Rifles on the other hand...
Like you said, a well placed shot will get the job done, but unless you've really trained to fight with your handgun (getoffthex.com or tacticalresponse.com- see fighting pistol), it's more luck than anything. Honestly, 9mm round to the chest feels like a 10 lb. weight dropped from about 3 inches if you're lying on the ground. Only way it's going to kill you is if it hits a major vessel and you bleed out, or damages vital brain tissue. Again, most people can't hit those areas when the SHTF.