I find when I've got accustomed to doing something leading to a particular habit, the reason I am addicted to that habit is because my body has been programmed to that habit. One way to break a habit is to train my body to act in a different way.
For instance there's this library I use a lot. When I leave I usually turn left. Over the last two weeks I've been trying a new route which means turning right out of the building. I have observed that because I've got so used to going left, I have to consciously tell myself to go right otherwise my feet tend to do what they're used to.
Just yesterday as I was leaving I absent-mindedly went left then I remembered what I was doing and changed direction.
The easiest way I find to break a habit is to intend it. Then the Universe takes over and does the rest.
It's never too late to teach an old dog new tricks.
Related articles: Ascension - the Game of Snakes and Ladders; The Magic of Intention; These Feet Were Made for Walking; Kicking the Habit; Can a Leopard Change Her Spots?; You Can't Teach an Old Dog New Tricks