Deception is a contranym - that is, a word that means both itself and the opposite thing, as well.
In the phrase your deception was simple, who is doing the deceiving? And who is being deceived?
Your assumption as to which way to interpret that phrase might just reveal something very deep about your personality: do you, basically, associate yourself with a victim or a perpetrator?
In fact I may have just solved the whole how-do-we-tell-who-is-evil? problem.
But, on the other hand, I probably haven't.
Thing Not To Be Involved In Today: deception. This word comes from the Old French deceivre, from the Latin dēcipere, to ensnare, from capere, to take.