Some stores are playing games now by remodeling and moving some items around so you have to go to the inside isles. They did that in the store right across the street from where I used to live. They put the produce in the CENTER of the store.
Sounds like you are making list but just not sticking to them? If so, this would be the area you must work on first and foremost. Make a list before you go, take a pen and cross off each item on the list as you put it in your basket. Do not let yourself be tempted by impulse buying. If it is not on your list, you don't put it in your basket. Even if it means you have to go back the next day, but you may find that you don't need it afterall and can do without. Just remember to start a new list and put the item on that list for the next shopping trip.
Be firm with yourself, and do allow for a few extra trips to the store until you are comfortable with sticking to your list..
Never just pop into the grocery store (on the way home) unless you already have list in hand. It is amazing what we buy when we put stuff in our carts without giving it a lot of thought.... So go home, get your list and then come back to the store.
I know this takes time and discipline, but it may be the best way to stick to your lists.....
I hope this helps.