Struggle with advance embracing sweetheart (7)
I believe the answer is:
compete
'struggle' is the definition.
(I've seen this in another clue)
'advance embracing sweetheart' is the wordplay.
'advance' becomes 'come' (I've seen this in other clues).
'embracing' is an insertion indicator.
'sweetheart' becomes 'pet' (both are terms of endearment).
'come' going around 'pet' is 'COMPETE'.
'with' is the link.
(Other definitions for compete that I've seen before include "Take part in hope of winning" , "Take part in contest" , "Engage in a contest" , "Contend (for a prize)" , "Strive (against others)" .)