Jim Carrey's on-again/off-again 28-year-old girlfriend has committed suicide ... TMZ has learned.
Law enforcement tells TMZ, LAPD responded to a call in the L.A. area Monday night. We're told they went to a residence and found the body of Cathriona White.
Our sources say White left a suicide note addressed to Carrey which references their break up on Sept. 24. Cathriona tweeted on the 24th ... "Signing off Twitter, I hope I have been a light to my nearest and dearest."