I felt uncaring somehow in group of political extremists (7,6)
I believe the answer is:
lunatic fringe
'group of political extremists' is the definition.
'i felt uncaring somehow' is the wordplay.
'somehow' is an anagram indicator.
'i'+'felt'+'uncaring'='ifeltuncaring'
'ifeltuncaring' anagrammed gives 'LUNATIC FRINGE'.
'in' is the link.
(Other definitions for lunatic fringe that I've seen before include "fruitcakes around the edge?" , "People who support extreme views" , "Eccentric minority" , "Extreme members of group" , "Extreme party members" .)