I'm in the exact same boat. I'm 31, and my life slowly began to revolve around drinking and doing drugs. I was a bartender and that really doesn't help any it's part of the scene mostly.
You are completely right in how you feel drinking and drugs are holding you back from the life you want to be living, never doubt that because it's the truth. The things you want to achieve are on the other side of this.
You know that which is amazing! Now you have to decide how badly you want to change it. How badly you miss the joy of life, feeling fulfilled, feeling proud of yourself, and generally just feeling positively good?
It may take time, it's taken me a while to make the sober commitment (and I'm not speaking from expertise on sobriety only on the ****** drunken life I've lived up until now) but you have made the first step. Realizing it for what it is. Keep thinking about that, keep reflecting. Try going sober for a few weeks at a time and remark how you feel. It may help push you forward in your evolution away from all the destructiveness.
I truly wish you well, we are on the same path!!