Alcoholism and Alcohol abusers are different.
I would suggest you try what I do which is drink bottles. You drink less they cost a bit more and you get the drinking feeling without the drunken woe. 8 bottles of bud is 12 units 8 cans of stella is 24.
You have to ask yourself why you drink all 8 do you not get to 4 and think enough or does it grind away at you knowing there is another in the fridge? I have this problem with more than beer though, I don't buy cakes because I will eat the whole cake, I don't buy chocolate because I will eat it all. I buy less beer just to stop me from slamming my way through a case whilst playing BF3. I too don't need it but it's a bad habit :/ my life works perfectly fine just on sundays I can be a bit reckless with the beers.
The main thing you have to realise is that 50 units in a week is bad for you let alone in 2 days. There is a reason that medical and life insurance companies don't like it! It's bad for business because it's not good for your health.