My experience was very similar to yours. I had wanted to stop for a long time and then was able to early Dec 2010 after a move away from everyone I use to drink with. I was able to stay sober for about 90 days on my own will power and coming to SR, but to do this I was literally staying in my apartment every night and weekend. Basically, I had cut myself off from the world and was pretty sick of doing that and almost threw in the towel on sobriety.
I literally picked a day to start drinking again, which was after a week of training for work on the east coast. Almost everyone at the training function was drinking except for me and one other girl. I was making a point to tell everyone I wasn't drinking because I was not thinking of sobriety as long term, but just a break from my old out of control lifestyle.
Well on the 4th night after a group dinner, the girl asked me if I was in AA. At first I was offended and said, "Why would I be in AA? I'm only 28, isn't that for older alcoholics?" She then replied, "Well I've been sober in AA for 6 years and I'm only 25."
After that I really started picking her brain and finally realized that going to AA could only help. A couple weeks later I got the courage to go to AA and it has changed my life forever. I was able to learn about alcoholism and how to stay sober. I wouldn't have been able to do anything on my own without the help from a sponsor, help from other alcoholics, and being able to talk to others who were in my situation.
What I believe is that many can stop drinking by their own will power, but it is almost impossible to stay stopped. Some stay stopped for a couple hours, while others may be able to stay stopped for months. My breaking point was around 90 days before I was lucky enough to get a little help from the guy upstairs. I hope you can get the same help that I got because in AA I learned to enjoy life sober, and not just abstain by closing myself off from the world like I was doing before.