Just my observation after decades of personal experience...the more sweets you eat, the MORE you want. That's why you can't satisfy the feeling of wanting them.
Conversely, the less of them you eat, the LESS of them you want. However, this takes quite some time for the body to make this adjustment. But it can and will happen if stuck to.
In the meantime, try to scale back the sweets to lesser intense ones. And much smaller servings of the more intense ones. Substitute complex starches for the simple sugars. Increase intake of KNOWN "good-for-you" foods such as veggies, whole grains, yogurts, etc. and try a little more protein; also, even a small amount of fat will help fill up the empty feeling.
Oh, and for anyone who thinks eating plenty of sweets is great and who has no concerns...well...I'm not directing my comments to them.