I'm another *ahem* older woman with wonky knees that I blame on my love affair with 3" heels that I always wore when I was younger. The standing, and the running up and down stairs carrying an armful of papers and books, though, finally took their toil when I also tore an ACL a few years ago. I recovered, to an extent, by faithfully doing my exercises but, if you are older, that knee never really goes back to the way it was before the accident. I'm also starting to feel the twinges of arthritis if I overdo the running or skiing.
Being able to stay active means more to me these days than wearing 3" heels, so I've resolved to stay with lower heels. I wish I had been a bit smarter when I was younger and realized that even a "comfortable" high heel can result in knee and foot issues when you get older. Mobility is something that you take for granted until you don't have it, so I think you are wise to transfer your affections to lower heels. As you say, Shannon, no matter how pretty the shoe, it's just not worth compromising the healing process.