Once you figure out the tribe you belong to, you’ll know what motivates members of that tribe. Then you’ll be able to “sell” a better idea to yourself more easily.
For example, before you eat another triple scoop cone, you might say to yourself “Nothing tastes as good as being _____ feels.” Knowing your tribe you might fill in the blank with: being skinny, being healthy, being kosher, or whatever’s important to you. Maybe yours is a tribe of one and you just want to look better in your bat suit.
You may be able to make the sale to yourself; especially if at some level you don’t really want to eat that triple scoop cone in the first place, maybe just a single scoop will do the trick.