For the first time since leaving rehab in February, John Mulaney has returned to the stand-up stage.
The comedian, 38, performed at New York's City Winery on Monday, kicking off a week of socially distanced, vaccine-required appearances at the venue. The show, titled "From Scratch," is sold out (and has been since last week).
Mulaney didn't shy away from addressing his time in rehab during the show, several people in attendance shared on Twitter afterward.
Rolling Stone senior editor David Fear called the event "intense."
"90 mins that was mostly processing his intervention and rehab experience," Fear tweeted Monday night. "Remarkably raw, vulnerable, personal. 'When I'm alone, I realize I'm with the person who tried to kill me.' Hilarious, harrowing, brave, historic."
"just left John Mulaney's first post-rehab show at City Winery," Money senior writer Julia Glum wrote in a tweet. "I don't know much about comedy, but imho he did a great job... an excellent mix of humor and honesty. I'm rooting for u, dude."
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Another attendee called the show "truly brilliant" in a tweet.
Mulaney completed a 60-day rehab stay in February, PEOPLE previously reported, after he sought treatment in December following a relapse in his decades-long journey with addiction. PEOPLE reported at the time that Mulaney would continue his sobriety work as an outpatient.
On Monday, news broke that Mulaney and his wife Anna Marie Tendler have ended their six-year marriage.
Listen below to the episode of our daily podcast PEOPLE Every Day for more on John Mulaney and Anna Marie Tendler's surprising split.
"John will not have any further comment as he continues to focus on his recovery and getting back to work," his rep said in a statement to Page Six, which first reported their split.
"I am heartbroken that John has decided to end our marriage," Tendler said in a statement to PEOPLE through her rep. "I wish him support and success as he continues his recovery."
If you or someone you know is struggling with addiction, please contact the SAMHSA substance abuse helpline at 1-800-662-HELP.