I recommend the HDS 250 lumen Executive model.
If this women lives in part of the World that does not allow people to carry firearms a flash light is not going to help. Teach her skills such as situational awareness and avoidance.
The strobe feature is not going to help.
Having a high output flashlight in any part of the world is better than having nothing. I refer to the spineless law makers and enforcers in the UK where it's a sin to even think of "protecting" yourself and bad guys are rewarded rather than dealt with unless it's against the system.
The objective is deterrence and either fight or flight in this case flight. I have had my iPhone stolen out of my hand, dragged down the road by the car and unfortunately didn't have my light with me. If I did I could have gotten the license plate.
The streets of many places in the UK and other parts of the world are full of very bad and violent people. Acting as a police Officer will likely get you worse than robbed and bluffing often isn't an option. There are places I won't even go.
I ve had situations that when walking down a dark alley the HDS was my best defense, and it has saved me simply by the wow factor and intimidation as well as the Surefire E2DL 200 and 500 lumen model (no strobe).
Regarding the 250, depends on what tint you prefer as there is a variance among the coolness and most are too cool for much use outside of blinding someone however they are intense and unpleasant on the receiving end. If you're lucky you can find one that is not "too" cool but it's rare.
325 NLT has a more useful tint but not too warm and not too cool... very bright.
The High Noon is 200 lumens, like looking at the sun at noon hence the name and all three of these have a very similar beam reach at over 140 meters plus.
The Clicky or executive gives you limited function 3 level choices with maximum over ride if I remember correctly at any given time where the Rotary Tactical gives you max momentary, momentary strobe, and various other levels of constant on. You have 3 presets. With the "Rotary " you have 4 presets.
Elzetta are a company where you can choose various options and Malkoff you can choose tint in believe.
There are many many others but as mentioned above many factors have to be weighed including price...
I forgot to mention that with a decent flashlight you also increase your awareness around you and therefore can respond to any danger more quickly.
The other thing to think about is you get what you pay for... and when the device is for self protection you can't really put a price on that.
Great quality flashlights have saved my life in several different scenarios from walking in the dark late at night to working in busy traffic as well as riding a bicycle where the roads are skinny and cars don't care to crowd you.