How do you stop snacking?!

It's not the notion of a snack that can be problematic, but whether you are planning them into your total calories for the day. The old adage, "failure to plan is a plan for failure" works here.

It sounds like you are grazing, thus snacking has become a problem for you. Are you hungry or are you eating for other reasons? If you don't think three meals a day will work for you, then incorporate a planned snack, but reduce the calories in your meals. Of course, if you are not tracking your calories or planning your meals, you may want to start there.