Ben Affleck, who has long been open about hisfight against addiction, appeared to be publicly inebriated recently.

Photos from the night show the star wearing a dark suit and a Halloween skull mask over his face.

“Sobriety is difficult and elusive for everyone struggling with addiction,” a friend of Affleck tells PEOPLE. “Ben has acknowledged he’s going to slip up from time to time. It was never as if this was simply behind him.”

Ben Affleck.BG027/Bauer-Griffin/GC Images

Ben Affleck

Hours earlier, the actor addressed havingbeen in recovery for over a yearon social media after cracking a joke about his personal life.

“But let’s be serious for a moment and talk about something that is actually important,” he wrote. “I have been in recovery for over a year and part of that is helping out others. @themidnightmission is an incredible organization that helps those in need with housing, training, development and recovery.”

“I’m making a donation today because there are peoplebattling addictionevery day that don’t have the resources and need help,” he continued.

Affleck, who’sbeen in rehab multiple times, entered rehab again last August.

He stayed at the center, with onlybrief breaksto work out at home and attend business meetings, until October when hebroke his silenceabout his treatment in an emotional statement on Instagram.

“This week I completed a forty-day stay at a treatment center for alcohol addiction and remain in outpatient care,” Affleck revealed in the Oct. 4 post. “Battling any addiction is a lifelong and difficult struggle.”

“Because of that, one is never really in or out of treatment. It is full-time commitment,” he continued “I am fighting for myself and my family.”

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In a candid interview this March, Affleck toldTodayco-hostHoda Kotbthat it “doesn’t really bother” him to talk about his sobriety journey.

“Being an alcoholic, it’s part of my life, it’s something that I deal with,” said the actor. “It doesn’t have to subsume my whole identity and be everything but it is something that you have to work at.”

“I had a problem and I really want to address it and I take some pride in that,” he added. “It’s about yourself, your life, your family…we encounter these kinds of hurdlesand we have to deal with them.”

Ben Affleck.Roy Rochlin/WireImage

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“He is very open about how challenging it is for him and works on his sobriety daily,” a source previouslytold PEOPLE“Ben thinks of alcoholism as a disease—you shouldn’t be ashamed of a disease.”

Affleck is “very serious about his sobriety. It’s definitely not easy for Ben,” the insider added.

source: people.com