Great that you are working hard at this and have made such a great life choice. Dont worry about bumps in the road, they dont knock you off the path, they just test your suspension.
To avoid bad snacking, have good snacks to hand when you are hungry or waiting for a meal (especially for the evenings when you said you struggle - probably b/c hnger kicks in). If you eat nuts have bags of mixed nuts or mixed fruit around for such an occassion. I eat wee bars called G-Bars. you get different types but I think they are all wheat, gluten,daily free. average about 7g's protein a bar. I am on pumpkin seed ones just now.
Keep fighting the fight, and dont rule out this guy. Like you said, hes willing to try new things. That might mean a life changing new way of eating.
It isn't the mountains ahead that wear you out....Its the grain of sand in your shoe.