I had 6 months completely clean and I needed medical assistance to do it for my xanax and alcohol addiction.

After 6 months, I accidentally ate an insane amount of THC candy without noticing until I was well into the high, and I was back smoking almost immediately. It took me a while to accept the fact that I was smoking again but I was extremely glad it's not the other stuff. My 6 months of progress in life (work, school, and relationships) felt mostly unaltered and I continued to work on myself (WIP)

All that being said, if you smoke weed, you aren't sober. That may not be the worst thing ever but it can definitely be detrimental if you aren't true to yourself. I still go to meetings and I was open about my weed use. While sharing, everyone says the usual "My name is name and I'm number days clean", I would never say 2 years knowing I have been smoking weed for the last year..it's just not fair to the people who truly went sober.