The wife does most of the planning but with my input. We discuss what we would like to make and whether or not we're going to bring the BBQ, etc. If we're not grilling anything on a short trip, we don't load the BBQ for obvious reasons.
I've actually thought of making a list of the common things we make over and over to spur memory. You could have a section for breakfast, lunch, and dinner, and put about a dozen things in each category. You don't have to stick to the list, but it could be a good starting point and you can keep adding to it over time as you discover new recipes.