Only you can decide for sure whether you have an issue with alcoholism or not. There's a couple simple tests you can take at these sites:
http://www.aa.org/en_is_aa_for_you.cfm?PageID=71 http://www.alcoholscreening.org/
I've been sober for a couple years. I used to think I was just a heavy drinker and could control my drinking, but now I understand that I can never safely drink again.
Here's something to think about. You gave a mighty description of your drinking patterns and characteristics. To my knowledge, normal drinkers don't ever consider those things.