C.H.
M.,
I've had sugar addictions twice. The first time, 8 years ago, I got over it by doing without refined sugar for 2 weeks. Then I found I could indulge without it owning me.
The second time started a year ago, and it lasted for a year. I tried, numerous times, and could never get rid of it. The most stressful year of my life didn't help.
In visiting with a board-certified nutritionist, I found I am gluten intolerant. Since I wasn't digesting gluten properly, the partially digested gluten was getting into my blood stream--and my reading shows that the body views it as an opiate, hence the sugar cravings.
He took me off all grains (at least for a while). It sounds odd, but within 2 days all of my cravings were gone and my awful symptoms (from the gluten intolerance) were also gone within a week. I realize a high protein diet would be difficult as a vegetarian.
A few options might be clearing the house of refined sugar (and not buying it) for a couple of weeks, trying to increase the amount of protein (and decrease the carbs) you're eating, never snacking on just carbohydrate (add nuts or some kind of protein), or finding healthy foods you really like (maybe indulge in fresh berries) to eat when you crave the sugar.
Also, you might want to google candida . . . sometimes when folks have a systemic yeast/fungus they end up with sugar cravings.
Good luck!