King Lear and Gloucester are both old men who have been betrayed and cast out into the cold by their own children. In Lear's case it was his two daughters Goneril and Regan who treated him so cruelly that he preferred to become a homeless vagabond to being under obligation to them. In Gloucester's case, he was betrayed by his illegitimate son Edmund and believed erroneously that his legitimate son Edgar had been planning to dispossess him. Both Lear and Gloucester loved their children and feel heartbroken that they have been pitilessly repaid with contempt and scorn after all the years they had treated their children with loving kindness and had given them everything. Shakespeare is dramatizing a common human tragedy. Many parents find themselves unwanted and despised by their grown children who consider their elders a burden and a nuisance. In Measure for Measure, Shakespeare says:
Friend hast thou none,
For thine own bowels, which do call thee sire,
The mere effusion of thy proper loins,
Do curse the gout, serpigo, and the rheum,
For ending thee no sooner.