"We feel so excited and blessed to celebrate this happy day with our family and friends," the newlyweds said in a statement.
Smart walked down the aisle in a gorgeous Carolina Herrera gown while her eight (yes, eight!) bridesmaids wore navy Ann Taylor dresses.
The Shameless actress said the decision to get hitched in Traverse City was an easy one, since the city has been her "second home" since she was young and Oosterhouse is also from the area.
The couple met at a green-charity event in November 2010. The actress formerly dated star Branden Williams from 1994 to 2006.
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