I have been down this road before..
what feels good for a man does not always feel good for a woman.
you can save a lot of headache by letting her try diffrent ones before deciding on one for her..She needs to make the decision.
whether the caliber she chooses or the one you prefer are the same or diffrent.
also think about the intended use, home defense, range use, target, or concealed carry. Diffrent models exist for diffrent applications, both in semi auto and in revolvers.
I have yet to find the perfect handgun, one that is in a caliber that is sufficient, with a grip that points naturally, with a trigger that is comfortable, with enough weight that is pleasant to shoot, but not to much to be burdensome to carry, enough size to be able to tame muzzle flip and give a good sight radius, but small enough to conceal.
the reason for this is that it does not exist. All of them are a compromise
range guns tend to be bigger,heavier and are pleasant to shoot but are hard to conceal.
concealable guns tend to be lighter, in smaller calibers, smaller size overall, and have more recoil and are not as pleasant to shoot for a extended range trip.
there is a website called http://www.corneredcat.com/Contents/
that is written by Kathy Jackson that is written from a womans perspective and has lots of great info in it.
otherwise you'll pick a weapon for her depending on your tastes, and end up trading it in 5-6 times before you come to the conclusion that she needs to pick it out herself..
best of luck down this journey..