In Girls Versus Suits, Ted asks Cindy out on a date and when he comes to pick her up at her apartment, it turns out Cindy has serious issues with her roommate (who Future Ted reveals to be the Mother); her dates keep falling in love with her roommate, and her roommate's strange habits, which annoy Cindy.
During the date, Cindy explains more about the strange habits she dislikes about her roommate that Ted secretly thinks are awesome. Cindy tells how the Mother paints pictures of robots playing sports and has breakfast foods singing show tunes. Future Ted reveals the painting of robots playing volleyball is still hanging in the house and that an English muffin singing "Memories" is the most hauntingly beautiful thing he has heard to this day. Even though she complains about her roommate throughout the evening, Ted wants to continue dating Cindy.
After the date, Cindy tells Ted she can't see him again, blaming the University policy preventing students and lecturers from fraternizing, as she fears it could cost her her scholarship. At first Ted tries to rationalize her decision as being for the best, especially as the others point out that Cindy's future and Ted's job are in jeopardy. Ted is inspired to try again, and shows up at Cindy's apartment and tries to persuade her to go out with him again, unwilling to miss out on the chance of her being the right woman. She takes Ted to talk in her room as her roommate is just about to leave the shower. As he tries to convince Cindy that their paths are meant to cross, he picks out items from her room which show how much they have in common. Cindy reveals that all three objects are really connected to her roommate. Frustrated that Ted is already more compatible with her roommate, Cindy tells him to leave. Ted does not meet her roommate, although on his way out he does catch a glimpse of her feet, as she disappears into her bedroom. Ted forgets to take the yellow umbrella he brought with him, revealing how the Mother gets it back.
In Band or DJ?, when Ted meets Cindy and Casey on a train ride, in a flashforward from a week before Barney and Robin's Wedding, Cindy says that she recently had brunch with her "ex"-roommate, referring to The Mother. This means that The Mother moved out of the apartment sometime after the events of Girls Versus Suits, or Cindy no longer lives there.