Hi luvmyboyz,
I am a 47 year old man with Tourette's, and I have had this same tic for about 15 years now. Basically I contract my diaphram very suddenly, expelling air from my lungs. That feeling your son is talking about "not getting it" is the satisfying "scratching an itch" feeling you get from doing a tic. For some reason the tic isn't giving him that satisfying feeling, but that will probably come and go.
When I first started doing it when I was 29, it was pretty tiring, and I would feel drained after some time. But I have been pursuing various healing modalities since I was about 18, and my situation improves steadily year after year. At this point my tics are fairly mild, and have stabalized to about six or eight tics that I have been doing for about ten years now. The forceful exhalation tic is one of them, but I don't do it enough for it to make me tired.
I've never been a parent, but from what you are describing it sounds like it must be so very difficult what you are going through. I hope you find ways to take care of yourself, as well as your sons. That will ultimately help you help them too.
It sounds like you have good information channels here in these forums, so I won't get into suggesting too many things - I could go on and on about the things I've done over the years. But one thing that really helped me in my early years of my struggles was getting massage/bodywork. It helped me learn to relax, and to just settle down into my body. This wasn't a miracle cure, but over time I learned to actually feel good in my body, which was a tremendous help in the long run bigger picture. If your son is open to that kind of thing it might help...
