Taye Diggs, Kate Walsh

Addison Forbes Montgomery (Kate Walsh) has had quite the revolving door of men on Private Practice, though executive producer Shonda Rhimes says it's all for good purpose: "We're bringing her on a journey to get a chance to have a happy ending."

So, is the happy ending with Pete (Tim Daly), with whom Addison has been playing house this season, or Sam (Taye Diggs), whose pining has sent him into an angry tailspin?

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Although Addison has been in a relationship with Pete for the better part of Season 3, "it's really about the baby," Walsh tells TVGuide.com. "The baby is like the little carrot that's being dangled in front of Addison. She's super torn, but her affection is really about that baby."

Her affection also springs from her need to avoid being with Sam, says Walsh. "That tension with Sam is still there and lingering. It's always there, like avoiding the forbidden fruit."

"There will always be that kind of tension between these two characters just because of their history," adds Diggs, noting that he's been having fun playing the awkward moments with Walsh. "If you're in love with someone and see they're with someone else and playing family, it can get to you. Even though Sam has his own family, he feels like he's on the outside."

And Sam certainly has been on the outside this season, with Pete playing "a really good boyfriend to Addison," says Daly, adding she still has strong feelings for Sam "and it's a big mess."

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Addison's love life may be complicated now, but Rhimes insists that she has a shot at obtaining happiness in the near future. "I would love to see her in a healthy relationship," she says.

"She might put one foot down on the road to happiness," adds Walsh. "Like she dips her toes in the happiness pool, so hopefully in the fall she'll be full-on swimming in happiness."

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