"He's totally in love with Shauna and wants them to live together the moment he's home, then he'll make it official with a proposal," an insider told RadarOnline.com.
Things certainly seem to be heating up between Affleck, 46, and his 22-year-old Playboy girlfriend. Especially after she promised to give up her own boozy history in a bid of support for the Justice League star.
Sexton has also continued to support Affleck in person, as well, visiting him in his rehab facility – in spite of objections from the star's medical team.
"Ben insists he's got his sobriety under control and he's ready to check out soon," the insider added. "But he's phasing it in by having these day releases in the meantime."
Now, with his heart seemingly set on Sexton, Affleck is ready to pop the question.
"They've talked about this extensively and Shauna's full on board with it," the source revealed. "To her, dating Ben is like a fairytale and she's in this for the longterm."
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