Great little read: Prince of Lost Places by Kathy Hepinstall. After a child was killed in her son's school, Martha kidnaps him (ie: takes him away without her husband's knowledge). Martha plans to keep him safe from all the modern horrors that make a visit to the local McDonald's a risk of getting shot at and/or killed. Mother and son now live in a cave or are effectively homeless, dispite having a home they could go home to, should Martha give up life on the lam.
A man who is wandering the shores of the river where cave is located, could also be considered homeless. He too wants to forget about life for a while. Prince of Lost Places is truly a wonderful story.