Hi Lisa,
My only thought regarding your post is the giving up on the gym completely.
I was working out and doing aerobic exercise (recumbant bike) 5 days a week before treatment, but I did not completely stop during treatment.
I also did, and continue to do, stretching exercises for my jaw and neck (I had a neck dissection on one side), which I think were also helpful.
Granted, I did a very, very light workout (I didn't want to burn up very many of those precious calories), but I think it was at least a psycological victory to be able to keep up on the routine. Of course, if there are other circumstances preventing this, so be it.
I also did daily walks with my wife, which were also helpful.
Best wishes,
Chris