Walk away but if the person attacks, self defense is a must.
What martial arts does she practice? I'd recommend Judo or BJJ. These are very effective martial arts and it teaches how to actually submit somebody without necessarily harming them. Judo is more for men though while BJJ is ideal for the weaker sex and people generally physically not very strong. I've seen a woman flying arm bar a huge guy and made him cry like a baby while he tapped.
For a girl I wouldn't recommend boxing, karate and the likes. Wrestling is also good.
'the weaker sex'?
Please explain in a martial arts context. I've seen teenage females bring grown men to their knees in extreme pain causing them to tap out.....
Your post, really doesn't make much sense other
than to stroke your own ego as usual.
You for sure are not a martial artist.