To return to her is not the same (5)
I believe the answer is:
other
'not the same' is the definition.
(I've seen this before)
'to return to her' is the wordplay.
'to return' says the letters should be written backwards.
'to' back-to-front is 'ot'.
'ot'+'her'='OTHER'
'is' acts as a link.
(Other definitions for other that I've seen before include "Very unusual" , "Different; alternate" , "Different; additional" , "Alternative - unrelated" , "Different, not the same one or this one" .)