Much trouble accompanies married crushes (5)
I believe the answer is:
mills
'crushes' is the definition.
(mill is a kind of crush)
'much trouble accompanies married' is the wordplay.
'much trouble' becomes 'ills'.
'accompanies' says to put letters next to each other.
'married' becomes 'm'.
'ills' put after 'm' is 'MILLS'.
(Other definitions for mills that I've seen before include "Machines that grind or crush" , "Sir John - - (films)" , "Bomb" , "''Among these dark Satanic ...'' (William Blake)" , "factories" .)