You are probably correct in suspecting that there is something more to this, and someone else has already pointed out that you probably started seriously thinking about drinking again when you stopped taking the Antabuse. You had enough sense to wait until it was completely out of your system before drinking, after all.
Antabuse is an artificial barrier to drinking, much like residing in a place where alcohol is not available to consume. Possibly useful for a very short amount of time in the beginning, but ultimately unsuitable as a long-term solution for anyone determined to drink again.
I tried my share of artificial barriers, but they were just that -- artificial. If you seriously ask yourself why you felt the need for Antabuse in the first place, you may find the answer to why you drank again.
In the meantime, cut your losses before something bad does happen.