Remaining on topic...
I thought a little while on this and I think the Kershaw RAM may be right for her. It's a little small in my average sized male hands, so it might be just right in her's, it carries tip up for a quick draw, good G10 scales for grippiness. But more importantly, the action is super easy, i.e., it's very easy to open. It feels like an AO, but has none of the disadvantages. Within 15 minutes of playing with the RAM, she should be able to easily open the knife with a flick 100% of the time, even in stressful situations. In addition, the knive's flipper + finger choil provide some resistance to lock failure, a nice bonus. And you can find it for 50 dollars.
As a so-called "martial artist," I've grown a bit skeptical about much of the SD knife training I've seen in my life, including that in my own source style. Many SD knife guys train for knife battles, i.e., sword fights, and I just don't see that occurring very frequently. Furthermore, and this is true of a great many martial arts, you're training specifically against assailants that know your style. I.e., Tae Kwon Do fighters don't learn to fight just anyone, let's say, a Judoka for instance, they learn to fight specifically other TKD fighters. Their tactics will be supreme within the rules of their style, and other very similar styles (Shotokan Karate) but when the rules change abruptly, or their opponents do, they commit many serious mistakes that would have been no issue at all within the context of their source style (i.e., TKD fighters routinely stand directly in front of each other, hands down, kick each other, with no fear of getting whacked in the face).
Knife fighting in a lot of schools is like this. In my style, we had wooden tantos and actually sparred with them in light-medium contact, with very few rules (you can use any style you want, you can go to the ground, etc etc). But still, I learned to fight knowing that when I jumped forward a little, I could scare my opponent off, because he was reading my movements and protecting himself intelligently (for instance).
In real life, your opponent is probably not going to know how to react to your little movements and will just rush right in with no thought towards their own safety...the "straight blast" of knifing, if you will. This isn't hard to defend against, especially if you also have a knife, but it's not something you practice against often in these sort of MA sparring sessions (where you are also armed). This is precisely because talented martial artists tend not to be drugged up criminal losers.
One part of my training that WAS very useful to me, and perhaps to you, is disarming training, on a large variety of weapons. The assailant wears gear, and they are armed with a fake weapon of their choosing (or two, you don't know. Sometimes they put one in the back of their belt/pants etc and will pull it on you when fighting) and you wear no gear. You're allowed to go full force and use any means necessary, really, as an unarmed person, to disarm or disable your opponent. This is as close to the real deal as I can see it, since I can go full force against my attacker, I KNOW when I'm getting "stabbed" (it hurts--no gear) and this is a high resistance situation. No goofy play-along. This is the sort of training I might recommend.
But much of the SD training that I think is going to have a BIG effect on personal safety can be done pretty easily. Practicing drawing your knife/pepperspray/gun whatever you want constantly. The MOST important part of weapon based SD is the ability to deploy your weapon. Once it's out there, you have a lot of options, maybe even the opponent backing off, but if it's in your purse, you're still a vulnerable target. So put the weapon where you will carry it every single day, and deploy it, slowly at first, and as you get more accurate, get faster, until there's no thought at all. Hold the knife in your hands while you watch TV, flick it a lot, have some fun. Get comfortable with the tool. You want everything to be non-conscious by the time you need it. Basic attacks using a knife vary a lot depending on the style. In my style, we learned blade up and blade down, one knife and two knives at a time, but we did not learn the infamous icepick p'kal, and so I'm not educated enough to comment on that style, but people tell me it's very easy to learn.
But basically, the concept is pretty simple. The pointy end goes into your attacker. Extra points are given for face or throat. You might, as I do, turn your blade to be parallel to the ground for chest attacks to slide between ribs more easily. I mean, there's a lot to learn here, but unless she's interested in becoming a bona fide martial artist/mercenary/warrior type, stabbing people a lot will do. No reason to get fancy.
If you're interested in p'kal style (you can watch some youtube to see what it is) Spyderco makes a dedicated p'kal knife that should be good for it.
While we're at it, running is another good option if the distance is sufficient between you + assailant.
