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disillusionment; disillusion; disenchantment
理想と現実の差に幻滅を感じた。
I felt disillusioned by the gap between ideals and reality.
憧れの人物に会って幻滅した。
Meeting the person I admired, I became disillusioned.
幻滅を乗り越えてこそ本当の成長がある。
True growth comes only from overcoming disillusionment.