I was just looking for exactly this kind of information. I'm a 64 yr old grandma looking to learn more about smaller carry handguns for women.
I'm a 68 year old grandma, and a certified instructor for handguns and self defense. Don't let ANYONE tell you what the "best" gun is for a woman. Find out for yourself. First, take a basic pistol class of some kind, even if you had been shooting for years before. I learn more with each class I teach, and I suspect that any person who wants to use a gun can use a little refresher once in a while. The instructor will probably also be glad to help you find the right gun for you. This is especially true if you plan to buy a used gun. You need to be sure it is in good shape and doesn't have serious problems that might not be readily visible.
But you have to do the work of handling and shooting as many different guns as possible before you make up your mind. First, visit gun stores and handle a lot of guns. Find the one you feel good about, that fits your hand, that seems well balanced. You will know when you find one that feels "right." But you are not ready to buy it yet. You need to actually shoot it - or one just like it - first. What feels good in your hand may be too rough to shoot comfortably. You can do this by going to a gun range (or several of them) and renting that gun. Make sure that you can retain your grip as you shoot, and that the recoil is not so much that you become fatigued immediately. You do not want to buy a gun you are not going to be comfortable shooting, since frequent practice is the only way to be prepared to use it in an emergency.
Then make plans to do frequent dry fire and go to the range regularly to practice. Go with other women, if possible. Some instructors hold regular "clinics" so their previous students can get that practice in a safe and friendly environment. Ask your instructor if that is not offered during the class.
The "right gun" for a woman is exactly the same as it is for anyone else. Carry the largest caliber you can reliably control, and which is comfortable enough so that you are not discouraged from practice.
Then, after finding and becoming comfortable with shooting that gun, you will be ready to consider carrying it. Get more instruction if at all possible. And whatever method you choose, plan to practice faithfully. Carrying a gun is an awesome responsibility. The better you prepare for that, the more likely you are to be safe and happy with that decision.
I had to shoot a man to save my life more than 30 years ago. This is the story of that encounter:
The Man I Might Have Killed | The Price of Liberty I wrote a book based on that incident, and my subsequent efforts to arm and train myself so it might never happen again. I'll be glad to send a pdf copy of that small book to anyone who asks for it. Directions for that will be found at the bottom of the page linked.
Good luck, and I admire your determination to be responsible for your own safety.