Hi mspguy, I think you're right to be worried by the weekend drinking, because you're finding it hard to control it. Hiding it from your fiancee is also a red flag.
Good news is that you don't drink during the week so you only have the 2-3 days to worry about. It sounds like a stress release thing, and also a growing dependency which you may be predisposed to.
As an after-work drinker I had to avoid the usual triggers that made me crave a drink at a certain time of the day. I altered my routine slightly, walked some of the way home, had something to eat and drink right after work, and didn't let myself get too tired or hungry. Little steps helped a lot. See if planning activities where you can't drink (like a long trek), or camping, or staying in a hotel with your fiancee, works. You'll need to make a plan for yourself. Get very determined to break the cycle, and accept that you can't drink again, ever. This is easier if you break it down into shorter goals like, one weekend, six weeks, six months, a year and so on.
Trust me that if you can break the weekly drinking cycle it will take a huge weight off your mind.