Sugar makes you crave more sugar makes you crave more sugar makes you crave more sugar. Studies show that even drinking diet soda often leads to weight gain, because you are continuing the cycle of sweet cravings. I think you will hear this from a lot of chicks here. You are far from alone on this!
The good news is that you will also hear a lot of stories from chicks who have managed their sugar cravings successfully. Whether you choose a structured diet designed to reduce sugar cravings or you follow your own path, the way to reduce/eliminate sugar cravings is to reduce/eliminate sugar (and sugar substitutes) in your diet.
For cravings as strong as yours, eliminating sugar for a while may be your best bet. Cutting other simple carbs (white bread, etc.) will be helpful, too. And be sure to check the labels on any packaged or processed foods- you might be surprised at how much sugar (or corn syrup, etc.) is in these foods- spaghetti sauce, salad dressings, etc are LOADED with them. So even if you aren't eating ice cream, you are still fueling those sugar cravings if you eat such things.
Check out the forums for specific diets to find a lifestyle you can live with. Some of them have initiation/detox periods (like fatsmash and south beach) that really help you to fight the cravings and keep you eating healthy, filling foods.
I don't actually follow a particular diet, but eat mostly whole foods, no soda, and I rarely eat sweets. I used to crave sugar ALL THE TIME, and now I can take it or leave it. I NEVER would have imagined it. I still enjoy a little chocolate or ice cream once in a while, but its something to savor on occasion. I don't obsess about sweets anymore. Its become a non-issue. (now pasta is another story...)
I know cravings seem like they are beyond our control, but what you CAN control is what you actually choose to put into your mouth. You might really want or even crave soda or ice cream, but you CAN choose not to eat it. Keep making that choice and really, the cravings will lessen or even stop. I have read this from A LOT of people! If we can do it, so can you!!