If it makes you feel better you aren't the only one. My DH really tries though but he's very used to salt and fat so the meals I make aren't always satisfying. I'm happy to say he's not putting butter/Earth Balance on his toast and he's being a lot more mindful but it hasn't been an overnight change.
Just keep doing what you are doing and shining that example on him, he will see the change in you soon enough and follow suit, especially when he sees you enjoying all the food you eat.
As for your little munchkin, his age is the perfect time to get his diet correct. When mine were younger I had so much more control, but as they got older and were exposed to more junk it got a little out of control. But now we have found out that the baby (12 years now) has inherited my high cholesterol so DH is a lot more flexible with it, knowing that it's not only me but my son who needs to eat differently. It puts a whole new spin on things. Sometimes I get ticked off when I think about it though "when it was just me eating this way you cold care less about eating like me" but I'll take the blessing because it is what it is.
Anyway I know how frustrating it can be! You are in good company and have good support here!