Dave Allocca/Startraks Photo
09/19/2008 AT 10:45 AM EDT
says it was great to be directed by boyfriend Stuart Townsend in their new film Battle in Seattle
– except when it wasn't.
"No matter what I say, people think I am biased because I sleep with him," Theron joked with reporters in New York City Sept. 17. "It was great. He loved directing and I've never seen him so happy – which hurts my feelings as his girlfriend!"
Townsend, 35, Theron's boyfriend of seven years
, makes his writing and directorial debut with the drama about the 1999 World Trade Organization meeting in Seattle and protesters who brought the city's streets to a standstill.
Theron, 33, says Townsend spent five years writing and preparing for his labor of love. "We would go on vacation to Fiji," she says, "and I would be like, 'Romance time!' But he would have a pile of research and I would be like, 'Oh my God, this is so not sexy!' But that passion paid off."
For the Irish actor turned director, working with his real-life leading lady was fun, and occasionally embarrassing. "She called me by my pet name a couple of times," Townsend says. "The crew then started to call me by my pet name and I said to them, 'That's not cool. I'm trying to be a serious director here.'"
And what exactly is that pet name? "I can't tell you," says Townsend. RELATED ARTICLES:
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