I think it is great that you have not given up on yourself and are working so hard. About elipticals, I used to run on these things for some time and even though they are certainly lower impact (especially on the knees) I used to get lower back problems from these things. Might be my back which isn't that good, but that were my experiences. I always thought lowest impact would be a training bike. Ever tried one of these?
(I am also amazed that the text recognition programm works so well and apparently also gets the punctuation right)