It must be so hard for you to see him like this!
Sometimes vitamin/mineral deficiencies can affect emotional well-being as well as fatigue. I was recently very low on iron (not crohns related) and, in hindsight, I can see that it was affecting my outlook! This is certainly not the ONLY answer to how he's feeling but might be a contributing factor??? I'll tag Dusty and David... they may be able to suggest specific vitamins/minerals to be tested. The forum wiki also has quite a bit of info relating to vitamins/minerals.
I can also well imagine his disappointment re football!!! My son would feel the same way re his hockey.
I know he'll probably view it as 'second' best but perhaps if you and he can get some info re the athletics at university, you might be able to make him see it's an opportunity to explore new experiences. A friend's son played soccer his entire life, once his youth league ended (at 18), he began to join other sports - he now regrets that he never explored other sports and is loving the variety. Granted this boy wasn't 'forced' into this change by illness :voodoo: but, perhaps you can help your son see that there might be other sports he'll enjoy. Also, does his school have an intramural football league - these are often less intense/demanding than the competitive leagues (this is what my son plans to do with hockey).
Re the new school in general... does it have any upcoming 'visitor' or 'introductory' weekends or events? I know my son is hoping to register for an upcoming weekend event at his university which includes a weekend at the dorm, guided tours through the facilities and some social events to meet other new students. Does his school have anything like that? My son has also found some online forums re his new school and has already 'met' some students... Perhaps this might boost up his interest/excitement at going away to school??
Hope some of this helps... I'm sure it's heartbreaking for you to see him sad. :ghug: