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to bear a grudge against; to resent; to blame; to curse; to feel bitter towards
裏切った相手を何年も怨み続けた。
I held a grudge against the person who betrayed me for years.
人を怨むより自分を変えるほうが良い。
It is better to change yourself than to resent others.
怨むつもりはないが許すこともできない。
I do not intend to bear a grudge, but I cannot forgive either.