A gun is not a magic wand. Having one does not insure that you will not be injured or killed.
Imagine the disappointment should you draw your gun and attempt to fire only to have your weapon jam, especially if you could have escaped in those same few seconds.
Imagine the disappointment should you draw your gun and fire, only to see the attacker still coming at you and now drawing a gun of his own which you hadn't seen.
Imagine the disappointment should you draw your gun and fire several times, only to see that your attacker was not alone but has two accomplices.
You are never going to have perfect knowledge of what is going to happen. If running away provides you the best chance of being in control of your own destiny, then that is the course to choose.
If you are defending yourself and yourself alone, that is a choice you entitled to make. If it is another victim and you run, regardless of the odds, as far as I am concerned you are a coward.
I would rather imagine the disappointment on the aggressor's face when you pulled out your firearm and not only stopped a crime but in so doing prevented the young mother from being raped.
While were imagining things.....
And I mean you no offense.