Jim Carrey's Girlfriend Cathriona White Found Dead at Her Home, Note Found at Scene

Jim Carrey's girlfriend, 30-year-old Cathriona White, was found dead at her Sherman Oaks, California, residence on Monday night, the Los Angeles County Coroner confirms to ET.

White was found unresponsive by her friend who then called 911. She was pronounced dead at the scene and police confirm a note was also found there. Officials tell ET she may have died of a possible overdose. Her cause of death is being investigated as a suicide and an autopsy is likely.

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On what is believed to be her personal Twitter account, this cryptic message was posted on Sept. 24.

"Signing off Twitter," the tweet reads. "I hope I have been a light to my nearest and dearest. ✌?️❤️ to yo all."

Carrey's most recent tweet was a photo taken by White on Sept. 16. "I am nothing," the photo message reads. "What a relief."

The 53-year-old actor met White in 2012 and the two dated on and off for the last few years. They were most recently seen together in New York City on May 21, a day after the actor made an appearance on the finale of The Late Show With David Letterman.

If you or someone you know needs help, please call the National Suicide Prevention Lifeline at 1-800-273-TALK (8255).