lose one's emotional or mental composure
"She fell apart when her only child died"
go to pieces
"The lawn mower finally broke"
"The gears wore out"
"The old chair finally fell apart completely"
break or fall apart into fragments
"The cookies crumbled"
"The Sphinx is crumbling"
become separated into pieces or fragments
"The figurine broke"
"The freshly baked loaf fell apart"
To disintegrate, to break into pieces.