"It's been 10 years. There are so many times I still find myself wanting to tell you about something funny or strange or exciting," Moore said on Wednesday alongside a selfie of DJ AM smiling.
"I miss your contagious, guttural laugh and your hugs. The best hugs. Miss you every day but today is always hard," she continued.
Moore and DJ AM dated in 2007 and remained friends after splitting. DJ AM died in 2009 at the age of 36 from an accidental drug overdose.
Moore, who currently stars on NBC's This Is Us, also honored DJ AM on Instagram in 2018. "9 years. I miss you every day, Adam," she said.