I get strained terribly and fall apart (12)
I believe the answer is:
Here is my best explanation:
'fall apart' is the definition.
'i get strained terribly' is the subsidiary indication.
'terribly' indicates anagramming the letters.
'igetstrained' is an anagram of 'disintegrate'.
'and' is the link.
(Other definitions for disintegrate that I've seen before include "Shatter", "crumble", "Lose all cohesion", "Break into little pieces", "Decompose", "Crumble", "Fall apart - it isn't agreed (anag)" and "Go to pieces".)