I think the answers are all right. You have too much on your plate, you are tired (mentally & physcially) and thoughts of the problems with your son, are all depleting the interest and engergy needed for hobbies. I am retired and my children are grown but still I always feel like I must get my other work done and whatever resolved b/4 I take time for my sewing.
Of course I don't know the answer for you but the person who said to just take a small amount of time each day to sew had a good idea. Maybe it would relax you and you could then sew a little longer each time.
Good Luck!