Let me just add to the chorus, and say "Congrats" too...
There's been too many people i cared about, that i had to turn away from, because they couldn't even admit they were doing it in the first place, let alone that they had a problem. I know from my experience with drinking- if you're hooked, no matter what anyone else says or does, or what happens, you won't stop, unless you are truly ready to- or your body quits on you, whichever comes first... Be proud of yourself, Mark!
Give sorrow words: the grief that does not speak
Whispers the o'er-fraught heart and bids it break.
-William Shakespeare, Macbeth, Act IV, Sc. III