go to pieces
US /ɡoʊ tə ˈpiːsɪz/
UK /ɡoʊ tə ˈpiːsɪz/

1.
崩溃, 垮掉
to become so upset or nervous that you cannot function normally
:
•
After the accident, she completely went to pieces.
事故发生后,她彻底崩溃了。
•
He tends to go to pieces under pressure.
他一有压力就容易崩溃。