Mathew Perry's funeral is understood to have taken place in Los Angeles on Friday with US reports saying his Friends co-stars David Schwimmer, Jennifer Aniston, Courteney Cox, Matt LeBlanc and Lisa Kudrow were all in attendance.
Perry was found dead in a hot tub in his Los Angeles home on 28 October. A post mortem examination was inconclusive and officials are awaiting the results of toxicology tests.
Friends co-creator Marta Kauffman said she spoke to him two weeks ago and he was "in a really good place, which is why this seems so unfair".
She told NBC's Today show: "He wanted to help other addicts and it gave him purpose."
Friends co-creator David Crane agreed that helping other addicts "absolutely became his purpose, his reason for being".
Perry turned his $10m Malibu beach compound into Perry House, a men's sober living facility, in 2012, and the project received an award from the White House the following year.
He sold it two years later but said he was still committed to providing services for recovering addicts.
Others paying tribute in recent days have included fellow actor Hank Azaria, who said Perry had been like a "brother" and helped him stop drinking.
In a video posted on Instagram, he said: "The night I went into AA [Alcoholics Anonymous], Matthew brought me in.
"The whole first year I was sober, we went to meetings together and he was such a great... I got to tell him this. As a sober person he was so caring and giving and wise and he totally helped me get sober."
In a joint statement released on Monday, Perry's five Friends co-stars said they were "all so utterly devastated" by the news of his death.