In the Dave Ellis money program that I participated in the past two years, the key idea was to stop living in scarcity and move as firmly as possibly into living in sufficiency. Scarcity is a cultural underpinning in our society: never enough time, never enough money, never enough stuff. We consume time and money and stuff as if this will somehow save us from worry, from anxiety, from fear. It doesn't though, and most of us consume more instead of looking in a different direction for comfort and soothing.
I don't have, as far as I can tell, a shopping addiction. But since I stopped eating compulsively in mid-October, my desire to buy stuff has increased. Fortunately, this whetted appetite for stuff came at a time when I had a long dry spell in my paid work as an editor. With not much coming in, I needed to scale way back on what was going out. So my impulse didn't result in a lot of purchases and that helped me see what was going on.
There were a few things I needed and I bought them. But I sat through the ready response, the instant impluse to react to news of a new great book or something appealing in a catalog. I just let them pass. Sometimes it was easy, sometimes it was not. But I kept telling myself, "You already have enough."