Philip Seymour Hoffman
Mimi O'Donnell (3rd L), former partner of actor Phillip Seymour Hoffman, stands with their children Willa (in purple), Tallulah (4th L) and Cooper (R) as Hoffman's casket is loaded into a hearse following his funeral at St. Ignatius church in the Manhattan borough of New York February 7, 2014.Reuters

Philip Seymour Hoffman, who was found dead in his Manhattan apartment on Feb. 2 due to an apparent drug overdose, was caught up in a love triangle before his death.

Police officials on Tuesday found two diaries at his West Village apartment and in them, he detailed his heroin addiction and of being in love with two women.

The 46-year-old actor wrote about feeling "caught in between" long-time girlfriend Mimi O'Donnell and another woman he recently met.

The identity of the second woman has not been revealed, and it is not known when they met. But she is said to have caused a strain in their relationship, that started when Hoffman was directing "In Arabia We'd All Be Kings" in 1999. O'Donnell was the costume designer of the film.

This unidentified new woman is said to be one of the reasons why O'Donnell wanted him to move out of their Jane Street home three months before his death, Hoffman implied in his diary entries, New York Post's Page Six reported.

Also, O'Donnell did not want Hoffman around their children - son Cooper, 10, and daughters Tallulah, 7, and Willa, 5 — when he was using drugs.

In addition to penning details of his relationship with the new woman, Hoffman had also chronicled his descent into drug abuse. He wrote about his failure to control his addiction by attending Narcotics Anonymous meetings and expressed shame that he was drinking and abusing drugs after being sober for over two decades.

The diary entries are often hard to read, and sometimes sentences run into each other, according to reports.

"It's stream of consciousness and difficult to follow," one source who saw the entries told NBC News. "In one line he refers to 'Frank who always owes money,' and on the same page he writes about a 15-year-old girl from Texas."

"It seems he did at least part of it in rehab," said another source. "It definitely contained some soul-searching. But there is also a fair amount of rambling that doesn't make sense."