Sadly, never once meet again (9)
I believe the answer is:
reconvene
'meet again' is the definition.
('convene' is an answer for 'meet' so perhaps 'reconvene' is OK for 'meet again')
'sadly never once' is the wordplay.
'sadly' indicates anagramming the letters.
'never'+'once'='neveronce'
'neveronce' is an anagram of 'RECONVENE'.
(Other definitions for reconvene that I've seen before include "Meet again" , "get together again" .)