It started in college years, lots of party, lots of girls and PLENTY of drinks, specially beer.
Those days were fun, I got wasted, but only on those occasions.
I continued enjoyed beer after college, but gradually I started enjoying white wine and red wine during meals. Then, "because of the Summer heat" (Yeah, right...), I started drinking not one, but two beers at lunch. Then, I always drank 2 beers at lunch.
Then I started working at home some days and began drinking beer BEFORE lunch. This was the tipping point, I guess. By drinking before lunch, I'd go to lunch already with that tingling feeling, so add 2 more beers and I'd be perfect.
Of course, it only got worse. I started buying the cheapest supermarket brand beer, I chose, not the best, but the one with the most alcohol content - some 50cl 8% ABV german beer. Typical day I'd drink 5 or 6, which compares to 10 or 12 regular beers.