Check out the “Let it Snow” Xmas 2020 Group youtube project!”
Come What May from Moulin Rouge......
I did find it. You can buy the original version (the one from the soundtrack, by David Berwald) on Amazon but it's for the Kindle. I don't have a Kindle. So I got it another rather labor intensive way. But I'm glad I did, it's really beautiful. It was scored for piano / guitar and vocals. Yes, key of C.
I now see that it's available in hardcopy form, published by Hal Leonard HL00352377 Come What May...
I too LOVE the movie!