Time Travel and Body Swap short story identification

Question

Looking for a short story I probably read as part of an anthology in the early-mid 1990s.

The protagonist was a man living in the 'present', who suffers permanent pain from an injury (possibly involving diving or the water?), to the extent that he keeps a bottle of powerful painkillers next to his bed.

One day he wakes up pain-free, and finds himself in a utopian future. He meets a woman who introduces herself as the wife of the man whose body he currently inhabits. She explains that they are able to travel in time by switching minds with someone else.

The future is essentially perfect; there's no pain or disease, and people can swap bodies as needed to resolve medical issues. The protagonist sees this as effective immortality.

He then returns to his own body, and finds the pain is all the worse and harder to deal with for his time away.

The switching keeps happening, and he finds himself falling in love with the woman and the future. She complains that her husband is becoming bitter and cruel after his trips into the past, implied to be because of the pain he is experiencing.

The man plots to kill the time traveler by poisoning the pain pills, intending to kill his own body and 'trap' himself in the future.

After the next trip, however, he wakes up back in his own time but in a totally different, pain-free body. That is his last trip.

Important notes:

• I think that, at the time I read this, I probably had not seen Quantum Leap. I certainly didn't make the connection to the similarity between the stories. That would suggest this was late-80s or very early-90s.

• The man referred to his pain medications as "the dope" fairly frequently.

• The pain was a huge element in the story. It's the pain, and the hope of being free of it, that drives most of his actions.

Answer 1

Pillar to Post by John Wyndham.

The protagonist is Terry Molton. We don't find out what caused his problem. The story just says:

It had been just over four years since that mine had got me — four years, nine operations and more to come. Interesting for the doctors, no doubt, but it had turned me into just a hulk in a wheelchair, with only half of one leg and no feet at all under the blanket.

He wakes up one day and:

When I opened my eyes, there, in front of me, was the vision of the damsel. She didn’t have a dulcimer, and she certainly did not look Abyssinian, but she was singing, very quietly. It was an odd song, and for all I knew it might have been about Mount Abora, because I couldn’t understand a word of it.
...
I sat up suddenly, feeling my legs, both of them. There wasn’t any pain. But there were two legs and two feet!

The damsel is Clytassamine. As the transitions continue she complains of her husband that:

She sniffed. “It’s Hymorell. Your world has done something dreadful to him. When he came back, he was harsh and bitter. He kept talking of pain and suffering. I was afraid of him; he was—cruel.”

At the end:

I went to sleep despondently in the great green building, and when I awoke I was in this mental institution instead of either the future or the hospital. And I wasn’t in either Hymorell’s body or my own—I was in somebody else’s!