Confess means "to declare, own, or admit as true" and is closely related in meaning to grant and concede. When one confesses some crime or wrongdoing, he admits it and also accepts responsibility for the soundness of that admission."I confess that I have neglected you" implies that the speaker recognizes, or admits, guilt or shame for the neglect. When followed by the -ing form of a verb, confess takes the preposition to: "I confess to neglecting you." For further comment on admit and closely related words, See acknowledge, admit and admit, allow.
Dictionary of problem words and expressions. Harry Shaw. 1975.