The Playboy model, who had been spending time with the actor amid news that he and Lindsay Shookus, 38, had called it quits after one year of dating, hit back at a fan on Instagram who accused her of getting Affleck “thrown in rehab.”
“Never drank around or with him for the record,” Sexton said in a series of responses in the comments section of a photo of her drinking red wine.
“I love to drink and party! Absolutely dude. Most 22 year olds do,” she also wrote after the same fan said she was “arrested twice for underage drinking and public intoxication just last year.”
Sexton did not deny her past with alcohol, saying she had made “a dumb mistake and an embarrassing one at that.” However, the model double downed on her denial that she sent Affleck to rehab.
“Do these mistakes mean I would disrespect someone’s hard-earned sobriety by drinking with them or in front of them? Hell no. I have limitless respect for those who take action and actually do something about it,” Sexton wrote.
“With that being said, Ben is a grown ass man, baby. He makes his own decisions. Blaming a 22-year-old for someone’s 3rd time in rehab is just ridiculous. He is human. I am human,” she said.
Following news of his split from Saturday Night Live producer Shookus, Affleck and Shookus were spotted having dinner together at Nobu restaurant in Malibu and were later photographed grabbing Jack in the Box in Santa Monica.
“He is happy being able to date who he wants and not feel tied down to a serious relationship,” a source told PEOPLE at the time.
But days later, when Affleck’s ex Jennifer Garner — with whom he shares children Violet, 12, Seraphina, 9, and Samuel, 6 — was seen driving him to rehab for alcohol addiction, Sexton was photographed on a Malibu beach in a bikini.
PEOPLE confirmed Affleck, 46, entered rehab for alcohol addiction on Aug. 22. “He is seeking treatment. He knew he needed help and was vocal about it,” a source said.
Days leading to his return to rehab, an insider told PEOPLE: “Ben had been drinking alone for days. He was in bad shape. He had barely been eating and had not showered. It didn’t take much convincing. He wanted to go, and he cooperated.”
WATCH: Playboy Model Shauna Sexton Relaxed in a Bikini Hours Before Ben Affleck Checked Into Rehab
Several sources said Affleck had in fact been struggling again for months, though he had been going to meetings and working with a sober coach for much of the last year.
“He’s battled addiction for a long time now,” an Affleck source said, noting the star had been “constantly working on himself” but after splitting with Shookus in July “went into a darker and darker place until he had to reach out for help.”
If you or someone you know is in need of help, please contact the SAMHSA substance abuse helpline at 1-800-662-HELP.