Hi Alice,
I'm sorry to hear about what you are going though. I would like to offer some insight as someone who has hidden alcohol.
My problems with alcohol materialized from drinking on a regular basis in the evenings. I was very self-conscious about my drinking. I enjoyed it, and looked at it as a fun passtime, but did not want my wife to see how much I was drinking because she may "misinterpret" what I was doing as an alcohol problem. I wouldn't hide the fact that I was drinking, just how much. I tended to golp drinks when nobody was in the room or drink after my wife went to bed.
As my drinking progressed I started consuming more alcohol then we usually had around the house. This meant that if I wanted to keep having "fun" in the evenings without giving the wrong impression I needed to increase the amount of alcohol I was brining in to the house. This meant that in addition to hiding how much I was drinking I needed to worry about hiding the alcohol containers themselves. This further progressed to shopping at different stores so that none of the cashiers I was buying the alcohol from got the wrong impressions either.
The important thing to realise here is that the person being most deceived was me. In my mind I had my drinking under control, but I knew to an observer this would not appear to be the case. I'm not really sure what I would have done had my wife confronted me about the whole thing. I didn't really look at it like I was lying to her, rather I was avoiding trying to explain to her that I had it under control because she probably wouldn't believe that anyway.
What changed my actions was not a confrontation but simply me becoming sick of the way I was living. I was craving alcohol but not enjoying it anymore and the effort I was putting in to keep everyone from knowing how much I was drinking was exhausting. Had I not come to that realization I'm not sure what a confrontation would have led to, but I do know that I would have been arguing my side from a fictitious viewpoint that I totally believed.