Not quite sure how to break the dependency, but with respect to his food, can you dip his fruit into, say, some quinoa or something blended, present it to him with the new food 'hidden' on the other side of the fruit? You can also purchase freeze dried veggies, pulverize them and dip the fruit into the powdered veggies and offer the fruit pieces in a similar way.
I add a combo of flaxseed meal, hemp hearts and chia seeds and sprinkle it onto my flock's banana slices. Super healthy for them.
Just a few thoughts as to how to bump up his nutrition. Over time you can hopepfully reintroduce the food as separate very tiny pieces for him to hopefully pick through.