I went to a 4 day class that came with my machine. After that, I was able to load my quilts fairly well. I've had my machine for a year now and have done 18 quilts on it as well as some table toppers and runners and quite a few practice quilts with muslin. After each project, I felt that I had learned alot and although not always perfect, I was happy with my results. But the main thing is that after the first few quilts, I was beginning to really have fun. I am proud of the skills I am learning.
You might want to look into some of the online classes like at Longarm Classroom or Longarm University. There was one on loading your quilt. I have a handout from Cindy Roth at Longarm University called "Putting a Quilt on a Longarm Quilting Machine. Go to her site online.
I think you need to really use your longarm now that you are physically able to before you give it up. Do several practice quilts using pantographs or other techniques you wish to learn, but don't try to learn everything at once - give yourself time to enjoy what you are learning.