go off the deep end
- lose itSuccumb to overwhelming emotion
- snapSudden sharp sound
- meltdownCatastrophic loss of control
- breakdownFailure or decomposition
- unhingedMentally or emotionally unstable
crazy · frantic · hysterical · outburst · rage · tantrum · crack up · flip out · lose control · spiral · panic · overreact · explode · freakout · unravel · diving board · plunge · reckless
emotional/mental stability
go off the deep endkeep one's cool
Maintain emotional control
stay calm · keep it together · keep one's head · stay grounded · keep one's wits about one
behavioral restraint
go off the deep endhold back
Prevent forward movement
rein it in · play it safe · bite one's tongue · count to ten · sleep on it