You may recall how disheartened Mary was back in Rome (6)
I believe the answer is:
memory
'you' is the definition.
Both the definition and answer are singular nouns.
Maybe you can see a link between them that I can't see?
'recall how disheartened mary was back in rome' is the wordplay.
I cannot really understand how this works, but
an anagram of 'rome' is 'emor' which is present in the answer.
The remaining letters 'my' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
'may' acts as a link.
Can you help me to learn more?
(Other definitions for memory that I've seen before include "commemoration" , "reminiscences" , "(Computer) data store" , "Power of retaining and recalling past experience" , "Recollection" .)