Extravagantly perform part of lover, actually (7)
I believe the answer is:
overact
'extravagantly perform' is the definition.
'part of lover actually' is the wordplay.
'part of' indicates the answer is hidden within the clue.
'OVERACT' is hidden in the letters of 'lover actually'.
(Other definitions for overact that I've seen before include "Be excessive like fulsome thespian" , "Play role exaggeratedly" , "Be unsubtle on stage" , "Play (part) in an exaggerated manner" , "Exaggerate" .)