The question of responsibility is an interesting one. There is a real sense in which it might be said that none of the characters have responsibility for what happened to them, with two significant exceptions. Those exceptions concern the pride of the vicar and Randolph. Trying to find this burden of responsibility in the symbolism of the name "Twycott" is tricky because "Twycott" seems to be made up. "Twy-" though, is a variant on a prefix meaning "two." The surname "Cott" is considered a metonymy that was representative of the word for a coat of chain mail armour and that was given as a nickname to people who were "hard and unfeeling." This may be an appropriate analysis of the name Twycott as it applies to the vicar and to Randolf and a clue into the burden of responsibility.
Vicar Twycott may be seen to have been responsible for Sophy's and Sam's suffering because of hard heartedness on three counts: (1) asking Sophy to marry him when he knew he would be ashamed of her socially, "Mr. Twycott knew perfectly well that he had committed social suicide ..."; (2) not insisting upon Randolph showing respect and generosity to his mother's background and dialect, "her boy, with his aristocratic school-knowledge, his grammars, and his aversions, was losing those wide infantine sympathies, ... and drift[ing] ... away from [Sophy]"; (3) not providing for her financial autonomy and independence in his will, "Sophy had been treated like the child she was in nature though not in years. She was left with no control over anything that had been her husband's beyond her modest personal income."
Randolph has the burden of responsibility as one of the two hard and unfeeling characters. At an early age, as shown at the concert, he lost natural respect and affection for Sophy because of her village ways. Though she adapted to some of the refinements of the upper class, her speech always gave her away and made acquaintances less receptive of her. Later, as a solitary widow, she lost the refinements she had acquired, so Randolph grew more distant:
[She] became in her son's eyes--a mother whose mistakes and origin it was his painful lot as a gentleman to blush for. ... If he had lived at home with her he would have had all of [the yearning fondness that welled up and remained penned in her heart]; ....
His greatest responsibility is that he cruelly put his pride and his social status before any other consideration, very much in the same way as his father put his pride and social standing before other considerations; they are Twycotts.
Sophy and Sam may be said to have a shared responsibility in their fates in that their quarrel after their engagement opened the opportunity for both Sophy's accident and her marriage to Twycott. Perhaps the theme of this subtext is that havoc follows unresolved chaos in relationships, thus chaos in relationships must certainly be turned to harmony. Once things were set in motion, there was legally little or nothing Sophy could do to liberate herself from Randolph's tyranny. Similarly, Sam was legally bound to do nothing to liberate Sophy by his own actions.
Definately sophy, she was weak in descision making. Her first mistake was marrying the vicar. She did not love him but didn't see agood reason to refuse him. Her second mistake was not changing herself according to the society, if she had, life could have been happier. Her third mistake was letting her son have so much influence on her, sophy could have prevented that. She had no legal right to stand up and insist on marrying Sam. Judging from the points above it can be said that sophy was responsible for her own fate to quite a certain extent.
Sam hobson was not responsible for his own fate.He did what he could and it was not his fault that sophy refused to marry him, except that he quarreled with her.
the vicar and the son were not responsible for the little tragedies of their life but were responsible for other people's misery.