“ When one man has been under very remarkable obligations to another, with whom he subsequently quarrels, a common sense of decency, as it were, makes of the former a much severer enemy than a mere stranger would be. ”
 William Makepeace Thackeray, Vanity Fair (1847). copy citation

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“Of all Sedley's opponents in his debates with his creditors which now ensued, and harassed the feelings of the humiliated old gentleman so severely, that in six weeks he oldened more than he had done for fifteen years before—the most determined and obstinate seemed to be John Osborne, his old friend and neighbour—John Osborne, whom he had set up in life—who was under a hundred obligations to him—and whose son was to marry Sedley's daughter. Any one of these circumstances would account for the bitterness of Osborne's opposition. When one man has been under very remarkable obligations to another, with whom he subsequently quarrels, a common sense of decency, as it were, makes of the former a much severer enemy than a mere stranger would be. To account for your own hard-heartedness and ingratitude in such a case, you are bound to prove the other party's crime. It is not that you are selfish, brutal, and angry at the failure of a speculation—no, no—it is that your partner has led you into it by the basest treachery and with the most sinister motives.” source