I have been 100% free from drugs and alcohol for 29 years now. If I hadn't stopped, I would have been dead long ago. One of the best decisions I ever made. It's funny - I never ever get tempted to drink or use drugs, not even a little bit. But I still crave cigarettes often. That addiction is so strong. I love the smell of cigarette smoke (crazy, I know), and whenever I'm near smokers I want a cigarette so bad, even after all these decades of not smoking. Such an insidious horrible addiction.
It takes a lot of will power to not smoke cigarettes for me, but staying clear of everything else is no problem at all.
You definitely don't want to put all your eggs in one basket. No matter what, someday you will not be able to hike and you have to be able to pursue other things. I always figured if I couldn't hike I would pursue improving at musical instruments like Piano. I have quite a few things I am passionate about.
In my opinion it's all about: Get busy living.
ps - Alice Cooper is awesome, especially the Killer album!