I had to make a choice in life after I got two drunk driving arrests over a period of years. I could either quit drinking or I could quit driving. Driving was more important.
I and many of my friends smoked marijuana back in the day (When I grew up, I stopped). I ALWAYS new if I needed to be somewhere hours later, and if I did, I didn't smoke. I never wanted to compromise myself by letting something that I felt could be enjoyed responsibly be abused by getting behind the wheel.
And congrats on quitting drinking! How long have you been sober, if you don't mind me asking?