You have no choice, I put to killer I'm to reform (4,2,2,4,2)
I believe the answer is:
like it or lump it
'you have no choice' is the definition.
(phrase meaning someone must accept something)
'i put to killer i'm to reform' is the wordplay.
'to reform' indicates an anagram.
'i'+'put'+'to'+'killer'+'im'='iputtokillerim'
'iputtokillerim' anagrammed gives 'LIKE IT OR LUMP IT'.
(Other definitions for like it or lump it that I've seen before include "accept this willy-nilly" , "If not digging, stick" , "Enjoy it or put up with it (4,2,2,4,2)" , "You're stuck with that" , "Dismissive remark" .)