Hi Treadingwater,
Welcome to NT. I'm glad Sandy let you know about this place. Go to the MS forum on here. There are so many people there that can see you better and talk with you.
I think affection is the key to any problem, and any disease. Whether it is a 3 year old child, a young man or woman, or even an elderly person.
Love and affection, showing it that is, is the best gift a person who is feeling low can get. If you 3 year old hugs and kisses his Daddy, I am sure his eyes sparkle with delight. Both people get satisfaction from showing affection. Even is the smallest ways.
Giving advice and doing something about it, are two different things. It is hard on you too we realize, but both of you share the same problem in the end.
Get his smile back and the dark clouds over his head to go away and you won't feel so overwhelmed yourself. I do hope the doctor can give him a pill to fix things, but a hug goes a long way.
I hope everything works out for you and your DH. Nice to meet you.