gone off the deep end
- crazyMentally unhinged
- unhingedMentally or emotionally unstable
- snappedBroke with sudden force
- lost itSuddenly gave way emotionally
- meltdownCatastrophic loss of control
breakdown · cracked · bonkers · insane · unraveled · spiraling · hysterical · berserk · frantic · erratic · manic · unstable · wild · reckless · irrational · psychotic · flipped out · lost the plot
mental/emotional stability
gone off the deep endlevel-headed
Calm and sensible
clear-headed · well-adjusted · sensible · balanced · lucid