In the Prime universe, she is a teacher on Malcolm Reed's ship and ex-girlfriend of J. Hayes. She is married to Aidan MacKenzie. In the mirror universe, Susan and Aidan serve on the USS Defiant and serve under the Empress, Hoshi Sato (mirror). In that universe, she is ex-girlfriend to Douglas Jay Hayes Beckett.
On January 1 of 2176, Cheshire and MacKenzie discuss her drinking. Different decisions are made, depending upon which universe Cheshire and MacKenzie are in.