Cory was found dead on July 13 in 2013, at 31 years old after "intravenous heroin use combined with the ingestion of alcohol", according to a coroner's report at the time.
Michele's songs, "Hey You" and "If You Say So", are about Monteith. She has a small number 5, which was Monteith's character's football jersey number.
Reports have stated that this time of year is always hard for Lea Michele, as it reminds her of the love she lost.
"4 years and it still feels like yesterday. love you more C", she wrote in the caption, alongside a red heart emoji.
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Following his death, reps for Michele released a statement thanking fans for their support.
We are sending our thoughts and prayers to Lea and all of Cory's loved ones today.
Taking to Twitter, Michele posted a throwback Polaroid-style picture of the two together. And now Lea, who was dating Cory when he passed away, has shared an emotional tribute.
Currently, she is working on a television project called The Mayor.
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This undated photo provided by the Bucks County District Attorney's Office in Doylestown, Pa., shows Sean Kratz of Philadelphia . DiNardo's lawyer said his client confessed to the murders in exchange for prosecutors agreeing to not seek the death penalty .
'This is so lovely makes me cry, ' said one commenter, and another wrote: 'All my heart is with you and Him'.
Every year to the date, Michele honors his memory with a photo and a moving message.
The pair were said to be "happy and in love" in the days leading up to his death.
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