According to official documents obtained by the site, White, then 30, wrote the letter shortly after they split. "I've spent 3 days now in disbelief that you're not here. I can go on brokenhearted and try to put the pieces back. I could, I just don't have the will this time. I'm sorry you felt I wasn't there for you. I tried to give you my best part," she reportedly wrote, per TMZ.
"I don't really know about burial or that sort of thing. You are my family so whatever you choose will be fine," she continued. "Please forgive me. I'm just not for this world."
As previously reported, Carrey, 54, and the Ireland-born makeup artist began dating in 2012. White died of a drug overdose on September 28, 2015, after sharing several cryptic posts on her social media accounts. On September 1, she tweeted that she was "signing off" of Twitter.
The following month, the True Crimes actor attended White's funeral in her hometown of Cappawhite in Co Tipperary, Ireland. He was one of six pallbearers during the procession in town.
"I am shocked and deeply saddened by the passing of my sweet Cathriona," Carrey told Us Weekly in a statement at the time. "She was a truly kind and delicate Irish flower, too sensitive for this soil, to whom loving and being loved was all that sparkled. My heart goes out to her family and friends and to everyone who loved and cared about her. We have all been hit with a lightning bolt."
If you or someone you know is struggling, call the National Suicide Prevention Lifeline at 800-273-TALK (8255).
Sign up now for the Us Weekly newsletter to get breaking celebrity news, hot pics and more delivered straight to your inbox!