The Glee actress had been dating Cory when he passed away following a fatal cocktail of alcohol and heroin in a Vancouver, Canada hotel room.
Lea joined thousands around the globe in remembering Cory via Twitter today, saying: "Today we remember the laughter and joy you brought into our lives every day. We think of you always and love you so.
A similar post on Instagram read: "I know you would want us all laughing and smiling today.. So we think of you and remember all the laughter and joy we shared together. I hold you in my heart always and love and miss you so..." ❤️
The actress – who played Rachel in Glee - shared a similar comment on the anniversary of his death last year, saying: ""We hold you in our hearts today, and every day we remember your smile. We will love you and miss you always."
Cory was just 31 years old when he died.
Lea has frequently spoken about her love for Cory and believing that he is still watching over her.
She told Teen Vogue last year: "I somehow feel the insane love Cory and I had for each other morphed into this strength that I have right now.
"There's just something about knowing he's watching everything I'm doing and feeling like I have to do everything now not just for me but for him. I also have a safety net below me — if I fall or if it's too much, my friends and family will be there to catch me."
And the year before she told Ellen DeGeneres: "I literally lived every day of my life feeling like the luckiest girl in the whole world. l thought he was the greatest man."
"[My mum] told me at one point there is an empowerment that comes with grief. At some point you find it. It's hard but you'll find it. I think at a certain point you can choose to fall from this or choose to rise. I'm trying to do my best for him as I know that's what he would have wanted."
Watch Lea talking about Cory below: