The future of the world...

[Tartar Horde]

The Lone Wolf approach as opposed to the group, comes down to logistics in the long run. A well supplied family unit could live off stores cached, the duration of time that family unit survives is relative to the amount of food they have stored or can grow/scavenge etc. In one scenario the family has run out of food and so has to seek other people, groups to survive.
If on the other hand our "family" has the means to eventually put land into production growing cereals etc, just like the "homesteaders" did in the USA/Australia I see no reason why a Lone wolf family unit could not do the same. Ploughing the land would eventually have to be done with Horses or Oxen, where do you start! how many acres of cereal would one family need to supply both humans and Animals?