Mel Gibson and Robyn Moore Gibson were married for thirty years before filing for divorce. They split up in 2006 when Mel was arrested for drunk driving, but only officially filed for divorce in April 2009. It has been speculated that when Mel was spotted with singer-songwriter Oksana Grigorieva in March 2009 it was the final straw. Robyn received roughly half of Mel's fortune, which was around $425 million!