She doesn't show her true feelings (7)
I believe the answer is:
actress
'true feelings' is the definition.
Although both the answer and definition are singular nouns, I don't see how they can define each other.
'she doesn't show her' is the wordplay.
I cannot really see how this works, but
'show' could be 'act' (act is a kind of show) and 'act' is found in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for actress that I've seen before include "One on stage" , "one with a particular role?" , "Theatrical female" , "Female performer" , "eg Emma Thompson" .)