I'm going through almost the same thing you are, but to a little lesser extent now, as it's been 3 weeks since I left.
I was with her for a year and a half, we were engaged, but she just wouldn't stop drinking. She went to rehab, outpatient, psychologist, psychiatrist, AA, and got dry for a month and a half, then a relapse, dry for 2 weeks, another relapse, and another, until I couldn't take it anymore, I couldn't see myself going through the rest of my life like that. As much as I wanted to believe her that she's still serious about her recovery, I couldn't, as she said that while drinking.
So I left, and have been dealing with lots of guilt and pain, and grief for the loss of the sweet person behind the addiction, but it's starting to diminish, slowly.
We talked for a while after that, but then I said something regarding her drinking, and she broke contact. It's for the best, no good can come out of staying in touch, as much as we still both love each other, and I'm slowly realizing this.
You are going through the 5 stages of grief, and so am I. I'm still bouncing back and forth between the stages, mostly between anger, depression and bargaining, but now, after 3 weeks, I'm starting to see acceptance in the distance.
I too spent 2 weeks doing nothing but thing about her, all day long, but I'm finding myself doing that less and less.
Like any relationship that ends, it will take a while to get over, and I can't see myself dating anyone anytime soon, but I hope that in time I will be able to let go completely.