I think school sucks all of his energy and there's nothing left for home. He just wants to be alone. I can relate to this--he and I are both pretty low-energy and I could never go to work all day and then continue to do THAT sort of work at night.
First, I think that you are doing a fabulous job of figuring out how to support him and help him through this situation. Even without 2E struggles, I remember very well moments of panic where my mom stepped in and helped me understand how to get through school crunches. Much appreciated in hindsight.
I think you have stumbled upon a big problem with homework/projects for some students. The energy and learning required during the day leaves so little for the large workloads now expected at night (which seem so much larger than anything I remember as a student). By contrast, in college, the actual class hours are far fewer (given a reasonable course load) and leave time for studying and projects. That may be a vision that gives him hope!
