I have never had children, but I know that it is very difficult to see their children suffer. Whatever you do, don't go to the guilty route. You have nothing to feel guitly about.
You might want to ask your son what he wants. Like others have said, you could try the weekend to help him get comfortable at home. You might also ask if he wants to fly down to see you after he has healed a bit and before he goes back to work.
Take care of yourself and know that you can be for him fully when you are emotionally and physically healthy.
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