Self-deception: the act or state of deceiving oneself by refusing to acknowledge the truth about one's faults or actions.
彼は失敗を他人のせいにして自己欺瞞に陥っている。
He falls into self-deception by blaming others for his failures.
自己欺瞞を続けると、いつか現実と向き合わざるを得なくなる。
If you continue to deceive yourself, eventually you will have to face reality.
治療ではまず自己欺瞞を認めることが大切だ。
In therapy, it's important first to admit one's self-deception.