Adam:
Frank Millet and Archie Butt were old pals, shared a bachelor pad, and were travelling home together. These two would have known a great number of the passengers. It is said that Archie struck up a special friendship with Marian Thayer.
Edith Rosenbaum Russell knew a lot of her fellow merchants, department store buyers and other business people, and hung around with several, including George Rheims, Benjamin Forman and Robert W. Daniel. She also met most of the "big names" including the Astors, William Thomas Stead, Millet, Butt, the Harrises, the Duff Gordons and the Futrelles.
The Duff Gordons were friends with the Thayers and the Cavendishes. They also met and socialized with the Meyers and the Harrises. On the rescue ship they met Edith Rosenbaum, the Fortune women, Mrs. Kenyon, and the Allison nurse. As W.T. Stead was a friend of
Lucy Duff Gordon's sister, I think it's likely they knew each other as well.
And of course, Helen Churchill Candee is well known to have attracted a swarm of escorts, including Hugh Woolner, with whom there was possibly a romantic dalliance, Edward Kent and the ubiquitous Archibald Gracie.
Randy