I think this is a question that gets over looked. There's self-defense where I'm the only one in danger and then there's "Self-defense" when there may be a need to come to the aid of a family member or a child. Technically that's not classified as "self-defense." but in the case of family it could be very much self-defense in a broader perspective and the game plan for "self-defense" as a group is not the same as "self-defense" as individual.
I like to often show animals behavior for things like this because it's the most honest view and much of it is similar to what some of us would do. Or what is the best decision.
My personal thoughts is that Running away is good in some scenarios, but in others splitting from the group can be bad and the worst thing that one can do in terms of self-defense. In general, predators like prey that runs away, I believe humans are the same way. They look for the weaker of the group.
When I teach self-defense I teach for individuals and as a group. Usually I train mother and daughter individual techniques and methods and then I teach them how to operate as a team or a unit, to increase their safety as a group.