Hi Tammy
Wow, sounds really stressful for you!
I couldn't see how old your ss is? But just wondered if he went to nursery/school etc, as I wondered how he ate while away from the family?
By the sounds of things my ds eats a lot better at nursery than he does at home, and I think the whole peer pressure thing really helps. I wondered if it was possible for your ss to attend something like this, so you can assess how he is with food around other little people - it may help with teaching him that food is not only needed, but also social and fun?!
Just a thought - good luck!