The worse part of being sick isn't getting over it. It's getting back to where you feel normal like you were before you got sick. It's all you want to do, feel normal again. This is especially true and harder when you're old.
I had just gotten up to walking ~5 miles 4 days a week when this infection hit me and it will be into next week before I finish the drug and the side effects wane where I can start walking again, maybe earlier if I feel better.
But that's the point. It's not getting over an illness that matters, it's getting back to where you were when you became sick that matters.