That was fast!
The recovering alcoholic actor, 46, and his 22-year-old girlfriend were first spotted together in August, after his breakup from Saturday Night Live producer Lindsay Shookus, 38.
Sexton remained by his side as he returned to rehab that month, often visiting him at his Malibu facility.
Upon his release from inpatient treatment, he whisked her away just this past weekend to the country property he shares with ex-wife Jennifer Garner, 46.
A source previously told Radar his family, friends and counselors were concerned about Affleck's hot fling with the hard-partying young model.
"No one in his life thinks that he should be getting involved with Shauna," a source said last month.
Looks like perhaps he finally listened to advice. A source told People, who first broke news of the split, that he is now going to "focus on his sobriety."
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