The poor girl from Balance of Terror seems to have moved on from her loss
The character was actully written as "Mary Teller" originally - a new character. Much like Riley coming back, they scrambled to change the script when they realized the actor had already played a named character in a past episode. Shatner didn't get the memo and refers to her as Teller at one point during the episode.
The character, by canon, "Angela Martine" appeared in 3 episodes (total) including Balance of Terror, Shore Leave, and Turnabout Intruder (although, again, Shatner refers to her as Lieutenant Lisa in TI). She would have been in Space Seed, but her scenes were cut.
Anyway, the actress, Barbara Baldavin is married to Joseph D'Agosta, the casting director for TOS - she became a regular on Medical Center in the 70s and ultimately became a casting director, herself, working on Dynasty and Trapper John, M.D., among other work.
This post was edited on 8/31 at 12:14 pm