"I still miss him very much and I still have the empty feeling," Joe told ET Canada.
Monteith was found dead from an overdose of heroin and alcohol in a Vancouver hotel room last July. Joe had an estranged relationship with his son for the majority of his life, but the two had begun to tentatively reconnect in Monteith's final years. However, Monteith's mother, whom Joe divorced in 1989, didn't inform him of the funeral plans.
"I didn't get to go to his viewing, which, it would have meant a lot," Joe said.However, Monteith's mother has since reached out, offering to send Joe some of the late actor's possessions.
Now, Joe tries to focus on the positive memories of his son, and says he misses his son's charismatic presence most. "Cory was a likeable young man and if he was in the room, you'd be smiling," he said. "He enjoyed life. That's why I was so shocked about the outcome of everything."