I haven't read the other comments in this post, because when I posted about the same (well, similar) topic, I got a lot of hate from it. People saying, "why don't you just STOP? How about that? It's just soda. Jeez."
I. love. sweet drinks. In fact, I think I love sweet drinks more than I like food- and I loves me some food. But I came to a realization that I needed to stop drinking them so often. My problem was they were to available to me to be able to stop. So I needed an alternative, rather than to go cold turkey. And if anyone answer cold turkey as an answer, they do not understand addition, or that you can be addicted to a soda.
I switched to drinking Vitamin water Zeros, Sobe Zeros (or whatever the diet version of Sobe is called), etc. I do not know if these are healthy, but their calorie count is sub twelve for the entire container. This is what I use as an alternative to sodas. I still have the occasional pepsi, or whatever. But it's not in my life quite often, and I enjoy them now as an occasional treat rather than as a beverage staple.
Also, and this was a recent discovery for myself, is the distinction between thirst and hydration, and wanting something tasty to drink. When I cracked open a bottle of vita water, and downed half of the thing out of thirst, only to find that I wasn't enjoying the beverage, I asked myself why I wasn't drinking water if I was thirsty. Water is boring, dull, and doesn't hold a candle to lovely sweet beverages- yeah. But if you're thirsty, you're not going to be enjoying your beverage. You're going to be occupying your taste buds with something as you try to slate a thirst.
So what I do is I have a clear idea of what I want from my drink; hydration, or flavor. If it's flavor, I will enjoy a vita water zero. If it's hydration, I will force myself to go water over the other. If I really want a treat, I will then buy a soda.
This is how I try to wrestle with my addition to sweet drinks. I hope it helps, and acts as a guide for you. The rest is all in your hands, will power, act active decision making.