Sinatra dated - and bedded - quite a few much-younger women. Carly was 25 in '70. Frank was 55, and dating 28-yo Irene, whom he'd been seeing for 2 years already.
Link for Dan:
http://www.glamourgirlsofthesilverscreen.com/show/517/Irene+Tsu/index.html
Some info on the song's creation which suggests the 'scarf' and 'gavotte' bit might not actually be about THE guy:
Carly came to see Richard at his Laurel Canyon house in May of 1972, bearing a song she had just written, the gentle, somewhat folkie Ballad Of A Vain Man (she'd loved Dylan's Ballad Of A Thin Man).
The song had come together in four separate parts. First, she'd sketched out in her journal the beginning of a song called
Bless You, Ben (using the same melody as You're So Vain). Then, on a flight from L.A. to Palm Springs, she'd added another, totally unrelated line to her journal when her seat mate, musician Billy Mernit, looked into the cup on his tray and said, "Doesn't that shape look like clouds in my coffee?" Thirdly, at one point when
she was feeling vengeful about the men who'd emotionally laid her low, she'd scribbled another: "you're so vain, I bet you think this song is about you." Finally, everything came together at a party in L.A.
A man she knew walked in, with a certain attitude, "and I said to myself, This is exactly the person that you're so vain is about.
The song reflected her belle-of-the-ball year and a half, which had negatively affected her self-esteem more than it seemed on the surface. Carly had belt-notched all those coveted hotties - Cat Stevens, Kris Kristofferson, Warren Beatty,
Jack Nicholson, Mick Jagger, not to mention the unfamous ones (and her truly loved James Taylor) - and with her "extreme intelligence and worldy wit," Ellen observed, she had enjoyed the party. Yet, Ellen adds, "I don't think she knew how to do it from her heart." Jake agrees, "Those were all wrenching emotional affairs for her." Sexual revolution or not, she'd felt used.
http://www.girlslikeusthemusic.com/2010/08/chapter-12.html