Vera gets nothing but the greatest affection (4,4)

'the greatest affection' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.

'vera gets nothing' is the wordplay.
'vera' becomes 'true' (I can't justify this - if you can you should believe this answer much more).
'gets' is a charade indicator (letters next to each other).
'nothing' becomes 'love' (love means zero in tennis).
'true'+'love'='TRUE-LOVE'

'but' is the link.

Can you help me to learn more?