12th Annual Chrysalis Butterfly Ball - InsideActress Lea Michele is paying tribute to her former boyfriend and "Glee" co-star, the late Cory Monteith, on the third anniversary of his death.

As she's done in previous years, Michele marked the anniversary of Monteith's passing, July 13, 2013, with a heartfelt post on Instagram. Sharing a photo of the late actor walking on some rocks along a coastline, Michele wrote, "We may not have gotten to share a lifetime together.. But the memories.. they're the best of my life." The actress ended the post, "Love you Cory."

The actress also took to Twitter with a similar message, posting the same photo and writing, "I know everyday you're watching over me, and smiling. Love and miss you Cory, everyday, but today a little more."

In 2013, Monteith was found dead in his Vancouver hotel room, and his cause of death was attributed to a mixture of heroin and alcohol in his system. Earlier that year, the actor spent some time in a rehab facility to treat substance addiction, after relapsing. The 31-year-old had previously been open about his struggles with sobriety, revealing that he had been dealing with substance abuse issues since his teens and into his 20s.

Michele and Monteith met on the set of Fox hit "Glee" in 2009, and began dating in early 2012.

[via: Lea Michele, Lea Michele]

Photo credit: Michael Buckner via Getty Images