No, Derry will not get back to his seclusion.The brief association of Derry with Mr. Lamb boosted his self-confidence and helped him to respect his own self. The manner in which the old man made Derry realize the importance of his being self-dependent, of respecting himself and of holding on to hope helped Derry undergo a remarkable change. The new found self-esteem makes him tell his mother that his looks are not important.He starts believing in his strengths rather than his appearance.
It is not likely that the death of Mr. Lamb would take him back to his secluded life. This big change in him is definitely there to stay and would not be undone due to setbacks.
What is the Planning Process?