Left with broken heart — man you dumped not wanting to do anything (8)
I believe the answer is:
lethargy
'not wanting to do anything' is the definition.
(lacking the energy or desire to do anything)
'left with broken heart' is the wordplay.
'left' becomes 'lgy' (I can't justify this - if you can you should believe this answer much more).
'with' indicates putting letters inside.
'broken' indicates anagramming the letters.
'heart' is an anagram of 'ethar'.
'lgy' enclosing 'ethar' is 'LETHARGY'.
'man you dumped' acts as a link.
This may not be correct. Some or all of it may be part of another bit of the clue.
(Other definitions for lethargy that I've seen before include "Drowsy" , "Lassitude, languor" , "Lassitude, sluggishness" , "Weariness" , "Inertia" .)