After seven years, Ben Affleck is still amazed at his luck in finding Jennifer Garner.

"Any man who wants to have a marriage work needs to know who the boss is," the Argo actor-director, 40, recently said. "The smart thing about me is I know how great she is."

The Butter actress, 40, has become adept at helping Affleck balance a career with kids Violet, 6, Seraphina, 3, and Samuel, 7 months.

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"He tends to get wrapped up in work," says a Garner confidant. "Jennifer is the one who can get him out if it."

Adds the insider, "She has him figured out and will never let him down."

Affleck detailed exactly what it is that first drew him to Garner during a recent chat with The Hollywood Reporter.

"She truly is kind," he gushed. "She means no one any harm. She doesn't have ill will for any person. She's not competitive with other people."

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Thanks to Garner's unwavering support, Affleck says he's in an incredibly positive place right now.

"I'm very lucky . . . I feel tremendously grateful," he told Us at a screening of Argo earlier this week. "I have a great family. I'm very inspired by where my career is right now. I'm fortunate . . . I'm happy with where I am."

This article originally appeared on Jennifer Garner Has Ben Affleck "Figured Out"