In terms of nutritional value, there are plenty of vitamins and other supplements available at most grocery stores which can help replace nutrients you would usually get from fruits/veggies. In terms of ingredients/actual food, preserved foods (canned veggies, dried fruits, etc.) have about the same nutritional value and taste almost exactly the same.

I'd say that if you really care about him you should give him a chance, regardless of whether or not you're "embarrassed to be seen with him." Then, if you still can't get over it, just try to let him down easy.