I've taken drugs for pain.
I didn't feel good, I felt better, not good.
I also didn't enjoy them. I would have preferred to not need them.
Rush went out of his way to get more. I went out of my way to not need more.
I've taken drugs for pain as well, and like you, I was concerned about how much I took and that I stopped taking them when the pain lessened. But what if your pain never goes away? Never lessens? Then what do you do.
Rush had pain associated with his coccyx bone. Go read up on that. Read the horror stories of the pain people have from that and then come back here and compare your pain to that.